diff --git a/.gitignore b/.gitignore
index fa92dac5..75958cf3 100644
--- a/.gitignore
+++ b/.gitignore
@@ -130,3 +130,5 @@ dmypy.json
 
 # Mac stuff
 .DStore
+
+.vscode
\ No newline at end of file
diff --git a/README.md b/README.md
index 853ba8ef..a63706b5 100644
--- a/README.md
+++ b/README.md
@@ -103,7 +103,6 @@ The table below shows the metrics included in TextDescriptives and their attribu
 | `Doc._.readability`        | `readability` | Dict containing Flesch Reading Ease, Flesch-Kincaid Grade, SMOG, Gunning-Fog, Automated Readability Index, Coleman-Liau Index, LIX, and RIX readability metrics for the Doc. |
 | `Doc._.dependency_distance`        | `dependency_distance` | Dict containing the mean and standard deviation of the dependency distance and proportion adjacent dependency relations in the Doc.|
 `Span._.token_length`   | `descriptive_stats`                       | Dict containing mean, median, and std of token length in the span.                                |
-| `Span._.syllables`    | `descriptive_stats`                       | Dict containing mean, median, and std of number of syllables per token in the span.  |
 | `Span._.counts`        | `descriptive_stats` | Dict containing the number of tokens, number of unique tokens, proportion unique tokens, and number of characters in the span. |
 | `Span._.dependency_distance`        | `dependency_distance` | Dict containing the mean dependency distance and proportion adjacent dependency relations in the Doc.|
 | `Token._.dependency_distance`        | `dependency_distance` | Dict containing the dependency distance and whether the head word is adjacent for a Token.|
diff --git a/setup.py b/setup.py
index 93d9f4ee..68a39e52 100644
--- a/setup.py
+++ b/setup.py
@@ -22,7 +22,7 @@
     author="Lasse Hansen",
     author_email="lasseh0310@gmail.com",
     url="https://github.com/HLasse/textdescriptives",
-    packages=["spacy-textdescriptives"],
+    packages=["textdescriptives"],
     install_requires=[
         "spacy>=3.0.3",
         "numpy>=1.20.0",
diff --git a/textdescriptives/__init__.py b/textdescriptives/__init__.py
index 895d63b2..a0017310 100644
--- a/textdescriptives/__init__.py
+++ b/textdescriptives/__init__.py
@@ -1,2 +1,3 @@
 from .load_components import TextDescriptives
-from .extractor import extract_df
+from .components import DescriptiveStatistics, Readability, DependencyDistance
+from .extractor import extract_df, readability_cols, dependency_cols, descriptive_stats_cols
diff --git a/textdescriptives/components/__init__.py b/textdescriptives/components/__init__.py
index fcd6059d..8fa301b2 100644
--- a/textdescriptives/components/__init__.py
+++ b/textdescriptives/components/__init__.py
@@ -1,3 +1,3 @@
-from .readability import create_readability_component
-from .dependency_distance import create_dependency_distance_component
-from .descriptive_stats import create_descriptive_stats_component
+from .readability import Readability
+from .dependency_distance import DependencyDistance
+from .descriptive_stats import DescriptiveStatistics
diff --git a/textdescriptives/components/dependency_distance.py b/textdescriptives/components/dependency_distance.py
index 62015a5b..8a5dc5a4 100644
--- a/textdescriptives/components/dependency_distance.py
+++ b/textdescriptives/components/dependency_distance.py
@@ -46,6 +46,13 @@ def span_dependency(self, span: Span):
 
     def doc_dependency(self, doc: Doc):
         """Doc-level dependency distance aggregated on sentence level"""
+        if len(doc) == 0:
+            return {
+                "dependency_distance_mean": np.nan,
+                "dependency_distance_std": np.nan,
+                "prop_adjacent_dependency_relation_mean": np.nan,
+                "prop_adjacent_dependency_relation_std": np.nan,
+            }
         dep_dists, adj_deps = zip(
             *[sent._.dependency_distance.values() for sent in doc.sents]
         )
diff --git a/textdescriptives/components/descriptive_stats.py b/textdescriptives/components/descriptive_stats.py
index 585bdbcf..859ad5f0 100644
--- a/textdescriptives/components/descriptive_stats.py
+++ b/textdescriptives/components/descriptive_stats.py
@@ -9,6 +9,9 @@
 
 @Language.factory("descriptive_stats")
 def create_descriptive_stats_component(nlp: Language, name: str):
+    sentencizers = set(["sentencizer", "parser"])
+    if not sentencizers.intersection(set(nlp.pipe_names)):
+        nlp.add_pipe("sentencizer")  # add a sentencizer if not one in pipe
     return DescriptiveStatistics(nlp)
 
 
@@ -35,7 +38,7 @@ def __init__(self, nlp: Language):
             self.counts,
         ]
         for ext, fun in zip(extensions, ext_funs):
-            if ext not in ["_n_sentences", "sentence_length"]:
+            if ext not in ["_n_sentences", "sentence_length", "syllables"]:
                 if not Span.has_extension(ext):
                     Span.set_extension(ext, getter=fun)
             if not Doc.has_extension(ext):
@@ -60,7 +63,7 @@ def token_length(self, doc: Union[Doc, Span]):
             "token_length_std": np.std(token_lengths),
         }
 
-    def sentence_length(self, doc: Union[Doc, Span]):
+    def sentence_length(self, doc: Doc):
         """Return dict with measures of sentence length"""
         # get length of filtered tokens per sentence
         tokenized_sentences = [
@@ -78,7 +81,7 @@ def sentence_length(self, doc: Union[Doc, Span]):
             "sentence_length_std": np.std(len_sentences),
         }
 
-    def syllables(self, doc: Union[Doc, Span]):
+    def syllables(self, doc: Doc):
         """Return dict with measures of syllables per token"""
         n_syllables = doc._._n_syllables
         return {
@@ -95,12 +98,16 @@ def counts(self, doc: Union[Doc, Span], ignore_whitespace: bool = True):
         else:
             n_chars = len(doc.text)
 
+        if n_tokens == 0:
+            prop_unique_tokens = np.nan
+        else:
+            prop_unique_tokens = n_types / n_tokens
         out = {
             "n_tokens": n_tokens,
             "n_unique_tokens": n_types,
-            "percent_unique_tokens": n_types / n_tokens,
+            "proportion_unique_tokens": prop_unique_tokens,
             "n_characters": n_chars,
         }
         if type(doc) == Doc:
             out["n_sentences"] = doc._._n_sentences
-        return out
+        return out
\ No newline at end of file
diff --git a/textdescriptives/components/readability.py b/textdescriptives/components/readability.py
index f6315855..9e85d435 100644
--- a/textdescriptives/components/readability.py
+++ b/textdescriptives/components/readability.py
@@ -1,7 +1,10 @@
 """Calculation of various readability metrics"""
+from textdescriptives.components.utils import n_sentences
 from spacy.tokens import Doc
 from spacy.language import Language
 
+import numpy as np
+
 from .descriptive_stats import create_descriptive_stats_component
 
 
@@ -47,22 +50,22 @@ def _flesch_reading_ease(self, doc: Doc):
         Higher = easier to read
         Works best for English
         """
-        score = (
-            206.835
-            - (1.015 * doc._.sentence_length["sentence_length_mean"])
-            - (84.6 * doc._.syllables["syllables_per_token_mean"])
-        )
+        avg_sentence_length = doc._.sentence_length["sentence_length_mean"]
+        avg_syl_per_word = doc._.syllables["syllables_per_token_mean"]
+        if avg_sentence_length == 0 or avg_syl_per_word == 0:
+            return np.nan
+        score = 206.835 - (1.015 * avg_sentence_length) - (84.6 * avg_syl_per_word)
         return score
 
     def _flesch_kincaid_grade(self, doc: Doc):
         """
         Score = grade required to read the text
         """
-        score = (
-            0.39 * doc._.sentence_length["sentence_length_mean"]
-            + 11.8 * doc._.syllables["syllables_per_token_mean"]
-            - 15.59
-        )
+        avg_sentence_length = doc._.sentence_length["sentence_length_mean"]
+        avg_syl_per_word = doc._.syllables["syllables_per_token_mean"]
+        if avg_sentence_length == 0 or avg_syl_per_word == 0:
+            return np.nan
+        score = 0.39 * avg_sentence_length + 11.8 * avg_syl_per_word - 15.59
         return score
 
     def _smog(self, doc: Doc, hard_words: int):
@@ -70,25 +73,31 @@ def _smog(self, doc: Doc, hard_words: int):
         grade level = 1.043( sqrt(30 * (hard words /n sentences)) + 3.1291
         Preferably need 30+ sentences. Will not work with less than 4
         """
-        if doc._._n_sentences >= 3:
-            smog = (1.043 * (30 * (hard_words / doc._._n_sentences)) ** 0.5) + 3.1291
+        n_sentences = doc._._n_sentences
+        if n_sentences >= 3:
+            smog = (1.043 * (30 * (hard_words / n_sentences)) ** 0.5) + 3.1291
             return smog
         else:
-            return 0.0
+            return np.nan
 
     def _gunning_fog(self, doc, hard_words: int):
         """
         Grade level = 0.4 * ((avg_sentence_length) + (percentage hard words))
         hard words = 3+ syllables
         """
+        n_tokens = doc._._n_tokens
+        if n_tokens == 0:
+            return np.nan
         avg_sent_len = doc._.sentence_length["sentence_length_mean"]
-        percent_hard_words = (hard_words / doc._._n_tokens) * 100
+        percent_hard_words = (hard_words / n_tokens) * 100
         return 0.4 * (avg_sent_len + percent_hard_words)
 
     def _automated_readability_index(self, doc: Doc):
         """
         Score = grade required to read the text
         """
+        if len(doc) == 0:
+            return np.nan
         score = (
             4.71 * doc._.token_length["token_length_mean"]
             + 0.5 * doc._.sentence_length["sentence_length_mean"]
@@ -102,17 +111,26 @@ def _coleman_liau_index(self, doc: Doc):
             0.296 * avg num of sents pr 100 words -15.8
         Score = grade required to read the text
         """
+        n_tokens = doc._._n_tokens
+        if n_tokens == 0:
+            return np.nan
         l = doc._.token_length["token_length_mean"] * 100
-        s = (doc._._n_sentences / doc._.sentence_length["sentence_length_mean"]) * 100
+        s = (doc._._n_sentences / n_tokens) * 100
         return 0.0588 * l - 0.296 * s - 15.8
 
     def _lix(self, doc: Doc, long_words: int):
         """
         (n_words / n_sentences) + (n_words longer than 6 letters * 100) / n_words
         """
-        percent_long_words = long_words / doc._._n_tokens * 100
+        n_tokens = doc._._n_tokens
+        if n_tokens == 0:
+            return np.nan
+        percent_long_words = long_words / n_tokens * 100
         return doc._.sentence_length["sentence_length_mean"] + percent_long_words
 
     def _rix(self, doc: Doc, long_words: int):
         """n_long_words / n_sentences"""
-        return long_words / doc._._n_sentences
+        n_sentences = doc._._n_sentences
+        if n_sentences == 0:
+            return np.nan
+        return long_words / n_sentences
diff --git a/textdescriptives/components/utils.py b/textdescriptives/components/utils.py
index 5228e64a..5dbe9730 100644
--- a/textdescriptives/components/utils.py
+++ b/textdescriptives/components/utils.py
@@ -24,10 +24,11 @@ def n_tokens(doc: Union[Doc, Span]):
     return len(doc._._filtered_tokens)
 
 
-def n_syllables(doc: Union[Doc, Span]):
+def n_syllables(doc: Doc):
     """
     Return number of syllables per token
     """
+
     dic = Pyphen(lang=doc.lang_)
 
     def count_syl(token: Token):
diff --git a/textdescriptives/extractor.py b/textdescriptives/extractor.py
index b89cb3d3..6fe191f8 100644
--- a/textdescriptives/extractor.py
+++ b/textdescriptives/extractor.py
@@ -135,7 +135,7 @@ def extract_df(
     "syllables_per_token_std",
     "n_tokens",
     "n_unique_tokens",
-    "percent_unique_tokens",
+    "proportion_unique_tokens",
     "n_sentences",
     "n_characters",
 ]
diff --git a/textdescriptives/load_components.py b/textdescriptives/load_components.py
index cf016165..3536f34c 100644
--- a/textdescriptives/load_components.py
+++ b/textdescriptives/load_components.py
@@ -1,8 +1,8 @@
 """Adds all components to a spaCy pipeline"""
-from components import (
-    create_readability_component,
-    create_dependency_distance_component,
-    create_descriptive_stats_component,
+from .components import (
+    Readability,
+    DependencyDistance,
+    DescriptiveStatistics,
 )
 
 from spacy.language import Language
diff --git a/textdescriptives/subsetters.py b/textdescriptives/tests/__init__.py
similarity index 100%
rename from textdescriptives/subsetters.py
rename to textdescriptives/tests/__init__.py
diff --git a/textdescriptives/tests/books.py b/textdescriptives/tests/books.py
new file mode 100644
index 00000000..324188a8
--- /dev/null
+++ b/textdescriptives/tests/books.py
@@ -0,0 +1,511 @@
+"""These books and tests are borrowed from https://github.com/mholtzscher/spacy_readability"""
+
+oliver_twist = """Among other public buildings in a certain town, which for many reasons
+it will be prudent to refrain from mentioning, and to which I will
+assign no fictitious name, there is one anciently common to most towns,
+great or small: to wit, a workhouse; and in this workhouse was born; on
+a day and date which I need not trouble myself to repeat, inasmuch as
+it can be of no possible consequence to the reader, in this stage of
+the business at all events; the item of mortality whose name is
+prefixed to the head of this chapter.
+
+For a long time after it was ushered into this world of sorrow and
+trouble, by the parish surgeon, it remained a matter of considerable
+doubt whether the child would survive to bear any name at all; in which
+case it is somewhat more than probable that these memoirs would never
+have appeared; or, if they had, that being comprised within a couple of
+pages, they would have possessed the inestimable merit of being the
+most concise and faithful specimen of biography, extant in the
+literature of any age or country.
+
+Although I am not disposed to maintain that the being born in a
+workhouse, is in itself the most fortunate and enviable circumstance
+that can possibly befall a human being, I do mean to say that in this
+particular instance, it was the best thing for Oliver Twist that could
+by possibility have occurred.  The fact is, that there was considerable
+difficulty in inducing Oliver to take upon himself the office of
+respiration,--a troublesome practice, but one which custom has rendered
+necessary to our easy existence; and for some time he lay gasping on a
+little flock mattress, rather unequally poised between this world and
+the next: the balance being decidedly in favour of the latter.  Now,
+if, during this brief period, Oliver had been surrounded by careful
+grandmothers, anxious aunts, experienced nurses, and doctors of
+profound wisdom, he would most inevitably and indubitably have been
+killed in no time.  There being nobody by, however, but a pauper old
+woman, who was rendered rather misty by an unwonted allowance of beer;
+and a parish surgeon who did such matters by contract; Oliver and
+Nature fought out the point between them.  The result was, that, after
+a few struggles, Oliver breathed, sneezed, and proceeded to advertise
+to the inmates of the workhouse the fact of a new burden having been
+imposed  upon the parish, by setting up as loud a cry as could
+reasonably have been expected from a male infant who had not been
+possessed of that very useful appendage, a voice, for a much longer
+space of time than three minutes and a quarter.
+
+As Oliver gave this first proof of the free and proper action of his
+lungs, the patchwork coverlet which was carelessly flung over the iron
+bedstead, rustled; the pale face of a young woman was raised feebly
+from the pillow; and a faint voice imperfectly articulated the words,
+'Let me see the child, and die.'
+
+The surgeon had been sitting with his face turned towards the fire:
+giving the palms of his hands a warm and a rub alternately.  As the
+young woman spoke, he rose, and advancing to the bed's head, said, with
+more kindness than might have been expected of him:
+
+'Oh, you must not talk about dying yet.'
+
+'Lor bless her dear heart, no!' interposed the nurse, hastily
+depositing in her pocket a green glass bottle, the contents of which
+she had been tasting in a corner with evident satisfaction.
+
+'Lor bless her dear heart, when she has lived as long as I have, sir,
+and had thirteen children of her own, and all on 'em dead except two,
+and them in the wurkus with me, she'll know better than to take on in
+that way, bless her dear heart!  Think what it is to be a mother,
+there's a dear young lamb do.'
+
+Apparently this consolatory perspective of a mother's prospects failed
+in producing its due effect.  The patient shook her head, and stretched
+out her hand towards the child.
+
+The surgeon deposited it in her arms.  She imprinted her cold white
+lips passionately on its forehead; passed her hands over her face;
+gazed wildly round; shuddered; fell back--and died. They chafed her
+breast, hands, and temples; but the blood had stopped forever.  They
+talked of hope and comfort. They had been strangers too long.
+
+'It's all over, Mrs. Thingummy!' said the surgeon at last.
+
+'Ah, poor dear, so it is!' said the nurse, picking up the cork of the
+green bottle, which had fallen out on the pillow, as she stooped to
+take up the child.  'Poor dear!'
+
+'You needn't mind sending up to me, if the child cries, nurse,' said
+the surgeon, putting on his gloves with great deliberation. 'It's very
+likely it _will_ be troublesome. Give it a little gruel if it is.'  He
+put on his hat, and, pausing by the bed-side on his way to the door,
+added, 'She was a good-looking girl, too; where did she come from?'
+
+'She was brought here last night,' replied the old woman, 'by the
+overseer's order.  She was found lying in the street.  She had walked
+some distance, for her shoes were worn to pieces; but where she came
+from, or where she was going to, nobody knows.'
+
+The surgeon leaned over the body, and raised the left hand.  'The old
+story,' he said, shaking his head: 'no wedding-ring, I see. Ah!
+Good-night!'
+
+The medical gentleman walked away to dinner; and the nurse, having once
+more applied herself to the green bottle, sat down on a low chair
+before the fire, and proceeded to dress the infant.
+
+What an excellent example of the power of dress, young Oliver Twist
+was!  Wrapped in the blanket which had hitherto formed his only
+covering, he might have been the child of a nobleman or a beggar; it
+would have been hard for the haughtiest stranger to have assigned him
+his proper station in society.  But now that he was enveloped in the
+old calico robes which had grown yellow in the same service, he was
+badged and ticketed, and fell into his place at once--a parish
+child--the orphan of a workhouse--the humble, half-starved drudge--to
+be cuffed and buffeted through the world--despised by all, and pitied
+by none.
+
+Oliver cried lustily. If he could have known that he was an orphan,
+left to the tender mercies of church-wardens and overseers, perhaps he
+would have cried the louder."""
+
+secret_garden = """
+When Mary Lennox was sent to Misselthwaite Manor to live with her uncle
+everybody said she was the most disagreeable-looking child ever seen.
+It was true, too.  She had a little thin face and a little thin body,
+thin light hair and a sour expression.  Her hair was yellow, and her
+face was yellow because she had been born in India and had always been
+ill in one way or another.  Her father had held a position under the
+English Government and had always been busy and ill himself, and her
+mother had been a great beauty who cared only to go to parties and
+amuse herself with gay people.  She had not wanted a little girl at
+all, and when Mary was born she handed her over to the care of an Ayah,
+who was made to understand that if she wished to please the Mem Sahib
+she must keep the child out of sight as much as possible.  So when she
+was a sickly, fretful, ugly little baby she was kept out of the way,
+and when she became a sickly, fretful, toddling thing she was kept out
+of the way also.  She never remembered seeing familiarly anything but
+the dark faces of her Ayah and the other native servants, and as they
+always obeyed her and gave her her own way in everything, because the
+Mem Sahib would be angry if she was disturbed by her crying, by the
+time she was six years old she was as tyrannical and selfish a little
+pig as ever lived.  The young English governess who came to teach her
+to read and write disliked her so much that she gave up her place in
+three months, and when other governesses came to try to fill it they
+always went away in a shorter time than the first one.  So if Mary had
+not chosen to really want to know how to read books she would never
+have learned her letters at all.
+
+One frightfully hot morning, when she was about nine years old, she
+awakened feeling very cross, and she became crosser still when she saw
+that the servant who stood by her bedside was not her Ayah.
+
+"Why did you come?" she said to the strange woman.  "I will not let you
+stay.  Send my Ayah to me."
+
+The woman looked frightened, but she only stammered that the Ayah could
+not come and when Mary threw herself into a passion and beat and kicked
+her, she looked only more frightened and repeated that it was not
+possible for the Ayah to come to Missie Sahib.
+
+There was something mysterious in the air that morning.  Nothing was
+done in its regular order and several of the native servants seemed
+missing, while those whom Mary saw slunk or hurried about with ashy and
+scared faces.  But no one would tell her anything and her Ayah did not
+come.  She was actually left alone as the morning went on, and at last
+she wandered out into the garden and began to play by herself under a
+tree near the veranda.  She pretended that she was making a flower-bed,
+and she stuck big scarlet hibiscus blossoms into little heaps of earth,
+all the time growing more and more angry and muttering to herself the
+things she would say and the names she would call Saidie when she
+returned.
+
+"Pig! Pig! Daughter of Pigs!" she said, because to call a native a pig
+is the worst insult of all.
+
+She was grinding her teeth and saying this over and over again when she
+heard her mother come out on the veranda with some one.  She was with a
+fair young man and they stood talking together in low strange voices.
+Mary knew the fair young man who looked like a boy.  She had heard that
+he was a very young officer who had just come from England.  The child
+stared at him, but she stared most at her mother.  She always did this
+when she had a chance to see her, because the Mem Sahib--Mary used to
+call her that oftener than anything else--was such a tall, slim, pretty
+person and wore such lovely clothes.  Her hair was like curly silk and
+she had a delicate little nose which seemed to be disdaining things,
+and she had large laughing eyes.  All her clothes were thin and
+floating, and Mary said they were "full of lace." They looked fuller of
+lace than ever this morning, but her eyes were not laughing at all.
+They were large and scared and lifted imploringly to the fair boy
+officer's face.
+
+"Is it so very bad? Oh, is it?" Mary heard her say.
+
+"Awfully," the young man answered in a trembling voice.  "Awfully, Mrs.
+Lennox.  You ought to have gone to the hills two weeks ago."
+
+The Mem Sahib wrung her hands.
+
+"Oh, I know I ought!" she cried.  "I only stayed to go to that silly
+dinner party.  What a fool I was!"
+
+At that very moment such a loud sound of wailing broke out from the
+servants' quarters that she clutched the young man's arm, and Mary
+stood shivering from head to foot.  The wailing grew wilder and wilder.
+"What is it? What is it?" Mrs. Lennox gasped.
+
+"Some one has died," answered the boy officer.  "You did not say it had
+broken out among your servants."
+
+"I did not know!" the Mem Sahib cried.  "Come with me!  Come with me!"
+and she turned and ran into the house.
+
+After that, appalling things happened, and the mysteriousness of the
+morning was explained to Mary.  The cholera had broken out in its most
+fatal form and people were dying like flies.  The Ayah had been taken
+ill in the night, and it was because she had just died that the
+servants had wailed in the huts.  Before the next day three other
+servants were dead and others had run away in terror.  There was panic
+on every side, and dying people in all the bungalows.
+
+During the confusion and bewilderment of the second day Mary hid
+herself in the nursery and was forgotten by everyone.  Nobody thought
+of her, nobody wanted her, and strange things happened of which she
+knew nothing.  Mary alternately cried and slept through the hours.  She
+only knew that people were ill and that she heard mysterious and
+frightening sounds.  Once she crept into the dining-room and found it
+empty, though a partly finished meal was on the table and chairs and
+plates looked as if they had been hastily pushed back when the diners
+rose suddenly for some reason.  The child ate some fruit and biscuits,
+and being thirsty she drank a glass of wine which stood nearly filled.
+It was sweet, and she did not know how strong it was.  Very soon it
+made her intensely drowsy, and she went back to her nursery and shut
+herself in again, frightened by cries she heard in the huts and by the
+hurrying sound of feet.  The wine made her so sleepy that she could
+scarcely keep her eyes open and she lay down on her bed and knew
+nothing more for a long time.
+
+Many things happened during the hours in which she slept so heavily,
+but she was not disturbed by the wails and the sound of things being
+carried in and out of the bungalow.
+
+When she awakened she lay and stared at the wall.  The house was
+perfectly still.  She had never known it to be so silent before.  She
+heard neither voices nor footsteps, and wondered if everybody had got
+well of the cholera and all the trouble was over.  She wondered also
+who would take care of her now her Ayah was dead.  There would be a new
+Ayah, and perhaps she would know some new stories.  Mary had been
+rather tired of the old ones.  She did not cry because her nurse had
+died.  She was not an affectionate child and had never cared much for
+any one.  The noise and hurrying about and wailing over the cholera had
+frightened her, and she had been angry because no one seemed to
+remember that she was alive.  Everyone was too panic-stricken to think
+of a little girl no one was fond of.  When people had the cholera it
+seemed that they remembered nothing but themselves.  But if everyone
+had got well again, surely some one would remember and come to look for
+her.
+
+But no one came, and as she lay waiting the house seemed to grow more
+and more silent.  She heard something rustling on the matting and when
+she looked down she saw a little snake gliding along and watching her
+with eyes like jewels.  She was not frightened, because he was a
+harmless little thing who would not hurt her and he seemed in a hurry
+to get out of the room.  He slipped under the door as she watched him.
+
+"How queer and quiet it is," she said.  "It sounds as if there were no
+one in the bungalow but me and the snake."
+
+Almost the next minute she heard footsteps in the compound, and then on
+the veranda.  They were men's footsteps, and the men entered the
+bungalow and talked in low voices.  No one went to meet or speak to
+them and they seemed to open doors and look into rooms.  "What
+desolation!" she heard one voice say.  "That pretty, pretty woman!  I
+suppose the child, too.  I heard there was a child, though no one ever
+saw her."
+
+Mary was standing in the middle of the nursery when they opened the
+door a few minutes later.  She looked an ugly, cross little thing and
+was frowning because she was beginning to be hungry and feel
+disgracefully neglected.  The first man who came in was a large officer
+she had once seen talking to her father.  He looked tired and troubled,
+but when he saw her he was so startled that he almost jumped back.
+
+"Barney!" he cried out.  "There is a child here! A child alone! In a
+place like this! Mercy on us, who is she!"
+
+"I am Mary Lennox," the little girl said, drawing herself up stiffly.
+She thought the man was very rude to call her father's bungalow "A
+place like this!" "I fell asleep when everyone had the cholera and I
+have only just wakened up.  Why does nobody come?"
+
+"It is the child no one ever saw!" exclaimed the man, turning to his
+companions.  "She has actually been forgotten!"
+
+"Why was I forgotten?" Mary said, stamping her foot.  "Why does nobody
+come?"
+
+The young man whose name was Barney looked at her very sadly.  Mary
+even thought she saw him wink his eyes as if to wink tears away.
+
+"Poor little kid!" he said.  "There is nobody left to come."
+
+It was in that strange and sudden way that Mary found out that she had
+neither father nor mother left; that they had died and been carried
+away in the night, and that the few native servants who had not died
+also had left the house as quickly as they could get out of it, none of
+them even remembering that there was a Missie Sahib.  That was why the
+place was so quiet.  It was true that there was no one in the bungalow
+but herself and the little rustling snake."""
+
+flatland = """
+I call our world Flatland, not because we call it so, but to make its
+nature clearer to you, my happy readers, who are privileged to live in
+Space.
+
+Imagine a vast sheet of paper on which straight Lines, Triangles,
+Squares, Pentagons, Hexagons, and other figures, instead of remaining
+fixed in their places, move freely about, on or in the surface, but
+without the power of rising above or sinking below it, very much like
+shadows--only hard and with luminous edges--and you will then have a
+pretty correct notion of my country and countrymen.  Alas, a few years
+ago, I should have said "my universe":  but now my mind has been opened
+to higher views of things.
+
+In such a country, you will perceive at once that it is impossible that
+there should be anything of what you call a "solid" kind; but I dare
+say you will suppose that we could at least distinguish by sight the
+Triangles, Squares, and other figures, moving about as I have described
+them.  On the contrary, we could see nothing of the kind, not at least
+so as to distinguish one figure from another.  Nothing was visible, nor
+could be visible, to us, except Straight Lines; and the necessity of
+this I will speedily demonstrate.
+
+Place a penny on the middle of one of your tables in Space; and leaning
+over it, look down upon it.  It will appear a circle.
+
+But now, drawing back to the edge of the table, gradually lower your
+eye (thus bringing yourself more and more into the condition of the
+inhabitants of Flatland), and you will find the penny becoming more and
+more oval to your view, and at last when you have placed your eye
+exactly on the edge of the table (so that you are, as it were, actually
+a Flatlander) the penny will then have ceased to appear oval at all,
+and will have become, so far as you can see, a straight line.
+
+The same thing would happen if you were to treat in the same way a
+Triangle, or Square, or any other figure cut out of pasteboard.  As
+soon as you look at it with your eye on the edge on the table, you will
+find that it ceases to appear to you a figure, and that it becomes in
+appearance a straight line.  Take for example an equilateral
+Triangle--who represents with us a Tradesman of the respectable class.
+Fig. 1 represents the Tradesman as you would see him while you were
+bending over him from above; figs. 2 and 3 represent the Tradesman, as
+you would see him if your eye were close to the level, or all but on
+the level of the table; and if your eye were quite on the level of the
+table (and that is how we see him in Flatland) you would see nothing
+but a straight line.
+
+When I was in Spaceland I heard that your sailors have very similar
+experiences while they traverse your seas and discern some distant
+island or coast lying on the horizon.  The far-off land may have bays,
+forelands, angles in and out to any number and extent; yet at a
+distance you see none of these (unless indeed your sun shines bright
+upon them revealing the projections and retirements by means of light
+and shade), nothing but a grey unbroken line upon the water.
+
+Well, that is just what we see when one of our triangular or other
+acquaintances comes toward us in Flatland.  As there is neither sun
+with us, nor any light of such a kind as to make shadows, we have none
+of the helps to the sight that you have in Spaceland.  If our friend
+comes closer to us we see his line becomes larger; if he leaves us it
+becomes smaller:  but still he looks like a straight line; be he a
+Triangle, Square, Pentagon, Hexagon, Circle, what you will--a straight
+Line he looks and nothing else.
+
+You may perhaps ask how under these disadvantageous circumstances we
+are able to distinguish our friends from one another: but the answer to
+this very natural question will be more fitly and easily given when I
+come to describe the inhabitants of Flatland.  For the present let me
+defer this subject, and say a word or two about the climate and houses
+in our country."""
+
+grade_1 = """A train! A train!
+A train! A train!
+Could you, would you,
+On a train?
+Not on a train! Not in a tree!
+Not in a car! Sam! Let me be!
+I would not, could not, in a box.
+I could not, would not, with a fox.
+I will not eat them with a mouse.
+I will not eat them in a house.
+I will not eat them here or there.
+I will not eat them anywhere.
+I do not like green eggs and ham.
+I do not like them, Sam-I-am."""
+
+grade_2 = """Jonathan pushed back the big iron pot and stood up.
+There were no bears. But up the path came his father, carrying his gun. And with
+him were Jonathan's Uncle James and his Uncle Samuel, his Uncle John and his
+Uncle Peter. Jonathan had never in all his life been so glad to see the uncles.
+"Jonathan!'" said his father, "what a fright you have given us! Where have you
+been all this time?"
+"Coming over Hemlock Mountain," said Jonathan in a small voice. And he ran
+right into his father's arms."""
+
+grade_3 = """For months I had been telling myself that I would never put the Magic Finger
+upon anyone again—not after what happened to my teacher, old Mrs. Winter.
+Poor old Mrs. Winter.
+One day we were in class, and she was teaching us spelling. "Stand up," she said
+to me, "and spell kat."
+"That's an easy one," I said. "K-a-t."
+"You are a stupid little girl!" Mrs. Winter said.
+"I am not a stupid little girl!" I cried. "I am a very nice little girl!"
+"Go and stand in the corner," Mrs. Winter said.
+Then I got cross, and I saw red, and I put the Magic Finger on Mrs. Winter good
+and strong, and almost at once...
+Guess what?
+Whiskers began growing out of her face! They were long black whiskers, just
+like the little ones you see on a kat, only much bigger. And how fast they grew!
+Before we had time to think, they were out to her ears!"""
+
+grade_4 = """The wheelbarrow picked up speed, so quickly that it sort of kicked up like a
+whipped horse. I thought the handle was going to rip right out of my fingers.
+"Hang on," I said.
+"If I can," said Soup.
+We were running now, full speed, smack down Sutter's Hill and heading full tilt
+toward the party. Ahead of us, the giant pumpkin bounced around inside the bin
+of the barrow. I felt like we'd stolen the moon.
+"We're out of control!" yelled Soup.
+"Turn it. Do anything, anything!"
+"Can't."
+The front door of the Baptist Church grew bigger and bigger, rushing toward us
+like a mad monster. My feet hardly touched the ground. I was too frightened to
+hang on much longer, yet frightened even more to let loose. Soup was screaming
+and so was I.
+"Stop," wailed Soup.
+From the street, there was one step up to the door of the Baptist Church. The
+door was closed."""
+
+grade_6 = """"Brothers. What do you expect of me—to stand idly by while you burn my son?
+My son has brought death to none of us. The scratches he gave us are not on our
+bodies but our pride. Brothers. How if my son is burnt do I go back and face her
+who lives with me in my house? How do I look in the eyes of his sisters who
+think the rainbow arches over him? Brothers. It is easier for me to fight you all
+than go back and say that Cuyloga stood by and did nothing while his brothers
+in anger put his son to the fire."
+With the quickness of Long Tail, the panther, he took his knife and cut the boy's
+thongs. Then he stood there waiting for the attack, but none came. The warriors 
+were too astonished. They watched, sullen and yet fascinated by the drama. This
+was the great Cuyloga at his bravest that they looked upon, and none knew what
+he would do next"""
+
+grade_8 = """All day Buck brooded by the pool or roamed restlessly about the camp. Death,
+as a cessation of movement, as a passing out and away from the lives of the
+living, he knew, and he knew John Thornton was dead. It left a great void in him
+somewhat akin to hunger, but a void which ached and ached, and which food
+could not fill. At times when he paused to contemplate the carcasses of the
+Yeehats, he forgot the pain of it; and at such times he was aware of a great pride
+in himself—a pride greater than any he had yet experienced. He had killed man,
+the noblest game of all, and he had killed in the face of the law of club and fang.
+He sniffed the bodies curiously. They had died so easily. I was harder to kill a
+husky dog than them. They were no match at all, were it not for their arrows and
+spears and clubs. Thenceforward he would be unafraid of them except when
+they bore in their hands their arrows, spears, and clubs."""
+
+grade_10 = """Looking upward, I surveyed the ceiling of my prison. It was some thirty or forty
+feet overhead, and constructed much as the side walls. In one of its panels a very
+singular figure riveted my whole attention. It was the painted figure of Time as
+he is commonly represented, save that, in lieu of a scythe, he held what, at a
+casual glance, I supposed to be the pictured image of a huge pendulum, such as
+we see on antique clocks. There was something, however, in the appearance of
+this machine which caused me to regard it more attentively. While I gazed
+directly upward at it (for its position was immediately over my own) I fancied
+that I saw it in motion. In an instant afterward the fancy was confirmed. Its
+sweep was brief, and of course slow. I watched it for some minutes somewhat in
+fear, but more in wonder. Wearied at length with observing its dull movement, I
+turned my eyes upon the other objects in the cell.
+A slight noise attracted my notice, and, looking to the floor, I saw several
+enormous rats traversing it. They had issued from the wall which lay just within
+view to my right."""
+
+grade_12 = """For the rest he lived solitary, but not misanthropic, with his books and his
+collection, classing and arranging specimens, corresponding with entomologists
+in Europe, writing up a descriptive catalogue of his treasures. Such was the
+history of the man whom I had come to consult upon Jim's case without any
+definite hope. Simply to hear what he would have to say would have been a
+relief. I was very anxious, but I respected the intense, almost passionate,
+absorption with which he looked at a butterfly, as though on the bronze sheen of
+these frail wings, in the white tracings, in the gorgeous markings, he could see
+other things, an image of something as perishable and defying destruction as
+these delicate and lifeless tissues displaying a splendour unmarked by death.
+"Marvellous!" he repeated, looking up at me. "Look! The beauty—but that is
+nothing—look at the accuracy, the harmony. And so fragile! And so strong! And
+so exact! This is Nature—the balance of colossal forces. Every star is so—and
+every blade of grass stands so—the mighty Kosmos in perfect equilibrium
+produces—this. This wonder; this masterpiece of Nature—the great artist.\""""
+
+grade_14 = """It would have been in consonance with the spirit of Captain Vere should
+he on this occasion have concealed nothing from the condemned one;
+should he indeed have frankly disclosed to him the part he himself had
+played in bringing about the decision, at the same time revealing his
+actuated motives. On Billy's side it is not improbable that such a
+confession would have been received in much the same spirit that
+prompted it. Not without a sort of joy indeed he might have appreciated
+the brave opinion of him implied in his captain making such a confidant
+of him. Nor as to the sentence itself could he have been insensible that it
+was imparted to him as to one not afraid to die. Even more may have 
+Graded Text Samples
+Impact Information. Page 9
+been. Captain Vere in the end may have developed the passion
+sometimes latent under an exterior stoical or indifferent. He was old
+enough to have been Billy's father. The austere devotee of military duty,
+letting himself melt back into what remains primeval in our formalised
+humanity, may in the end have caught Billy to his heart, even as
+Abraham may have caught young Isaac on the brink of resolutely
+offering him up in obedience to the exacting behest. """
diff --git a/textdescriptives/tests/test_dependency_distance.py b/textdescriptives/tests/test_dependency_distance.py
new file mode 100644
index 00000000..308037af
--- /dev/null
+++ b/textdescriptives/tests/test_dependency_distance.py
@@ -0,0 +1,103 @@
+import spacy
+import pytest
+from textdescriptives.components import DependencyDistance
+from .books import *
+import numpy as np
+import ftfy
+
+
+@pytest.fixture(scope="function")
+def nlp():
+    nlp = spacy.load("en_core_web_sm")
+    nlp.add_pipe("dependency_distance")
+    return nlp
+
+
+def test_dependency_distance_integration(nlp):
+    assert "dependency_distance" == nlp.pipe_names[-1]
+
+
+def test_dependency_distance(nlp):
+    doc = nlp("This is a short and simple sentence")
+    assert doc._.dependency_distance
+    assert doc[0:3]._.dependency_distance
+    assert doc[0]._.dependency_distance
+
+
+@pytest.mark.parametrize("text", ["", "#"])
+def test_dependency_distance_edge(text, nlp):
+    doc = nlp(text)
+    for v in doc._.dependency_distance.values():
+        v is np.nan
+
+
+@pytest.mark.parametrize(
+    "text,expected",
+    [
+        (oliver_twist, 3.19),
+        (secret_garden, 2.32),
+        (flatland, 3.42),
+    ],
+)
+def test_mean_dep_distance(text, expected, nlp):
+    text = ftfy.fix_text(text)
+    text = " ".join(text.split())
+    doc = nlp(text)
+    assert (
+        pytest.approx(expected, rel=1e-2)
+        == doc._.dependency_distance["dependency_distance_mean"]
+    )
+
+
+@pytest.mark.parametrize(
+    "text,expected",
+    [
+        (oliver_twist, 1.24),
+        (secret_garden, 0.85),
+        (flatland, 1.11),
+    ],
+)
+def test_std_dep_distance(text, expected, nlp):
+    text = ftfy.fix_text(text)
+    text = " ".join(text.split())
+    doc = nlp(text)
+    assert (
+        pytest.approx(expected, rel=1e-2)
+        == doc._.dependency_distance["dependency_distance_std"]
+    )
+
+
+@pytest.mark.parametrize(
+    "text,expected",
+    [
+        (oliver_twist, 0.41),
+        (secret_garden, 0.42),
+        (flatland, 0.45),
+    ],
+)
+def test_mean_adj_dep(text, expected, nlp):
+    text = ftfy.fix_text(text)
+    text = " ".join(text.split())
+    doc = nlp(text)
+    assert (
+        pytest.approx(expected, rel=1e-2)
+        == doc._.dependency_distance["prop_adjacent_dependency_relation_mean"]
+    )
+
+
+@pytest.mark.parametrize(
+    "text,expected",
+    [
+        (oliver_twist, 0.068),
+        (secret_garden, 0.098),
+        (flatland, 0.056),
+    ],
+)
+def test_std_adj_dep(text, expected, nlp):
+    text = ftfy.fix_text(text)
+    text = " ".join(text.split())
+    doc = nlp(text)
+    assert (
+        pytest.approx(expected, rel=1e-2)
+        == doc._.dependency_distance["prop_adjacent_dependency_relation_std"]
+    )
diff --git a/textdescriptives/tests/test_descriptive_stats.py b/textdescriptives/tests/test_descriptive_stats.py
new file mode 100644
index 00000000..d77698aa
--- /dev/null
+++ b/textdescriptives/tests/test_descriptive_stats.py
@@ -0,0 +1,84 @@
+from spacy.lang.en import English
+import pytest
+from textdescriptives.components import DescriptiveStatistics
+
+@pytest.fixture(scope="function")
+def nlp():
+    nlp = English()
+    nlp.add_pipe("sentencizer")
+    nlp.add_pipe("descriptive_stats")
+    return nlp
+
+def test_descriptive_stats_integration(nlp):
+    assert "descriptive_stats" == nlp.pipe_names[-1]
+
+
+def test_descriptive_stats(nlp):
+    doc = nlp("This is a short and simple sentence")
+    assert doc._.token_length
+    assert doc._.sentence_length
+    assert doc._.syllables
+    assert doc._.counts
+    assert doc[0:3]._.token_length
+    assert doc[0:3]._.counts
+
+
+def test_token_length(nlp):
+    doc = nlp("Gift cats your prey")
+    assert doc._.token_length["token_length_mean"] == 4.0
+    assert doc._.token_length["token_length_median"] == 4.0
+    assert doc._.token_length["token_length_std"] == 0.0
+    assert doc[0:2]._.token_length["token_length_mean"] == 4.0
+    assert doc[0:2]._.token_length["token_length_median"] == 4.0
+    assert doc[0:2]._.token_length["token_length_std"] == 0.0
+
+
+def test_sentence_length(nlp):
+    doc = nlp(
+        "Here is the first sentence. It was pretty short. Let's make another one that's slightly longer and more complex."
+    )
+    assert (
+        pytest.approx(6.33, rel=1e-2) == doc._.sentence_length["sentence_length_mean"]
+    )
+    assert (
+        pytest.approx(5.0, rel=1e-3) == doc._.sentence_length["sentence_length_median"]
+    )
+    assert pytest.approx(2.62, rel=1e-2) == doc._.sentence_length["sentence_length_std"]
+
+
+def test_syllables_simple(nlp):
+    doc = nlp("These words are easy")
+    assert doc._.syllables["syllables_per_token_mean"] == 1.0
+    assert doc._.syllables["syllables_per_token_median"] == 1.0
+    assert doc._.syllables["syllables_per_token_std"] == 0.0
+
+
+def test_syllables_complex(nlp):
+    doc = nlp("This sentence has complicated words in it")
+    assert pytest.approx(1.43, rel=1e-2) == doc._.syllables["syllables_per_token_mean"]
+    assert pytest.approx(1.0, rel=1e-3) == doc._.syllables["syllables_per_token_median"]
+    assert pytest.approx(0.73, rel=1e-2) == doc._.syllables["syllables_per_token_std"]
+
+
+def test_counts(nlp):
+    doc = nlp(
+        "Here is the first sentence. It was pretty short. Let's make another one that's slightly longer and more complex."
+    )
+    assert doc._.counts["n_tokens"] == 19
+    assert doc._.counts["n_unique_tokens"] == 19
+    assert doc._.counts["proportion_unique_tokens"] == 1.0
+    assert doc._.counts["n_characters"] == 94
+    assert doc._.counts["n_sentences"] == 3
+    assert doc[0:6]._.counts["n_tokens"] == 5
+    assert doc[0:6]._.counts["n_unique_tokens"] == 5
+    assert doc[0:6]._.counts["proportion_unique_tokens"] == 1.0
+    assert doc[0:6]._.counts["n_characters"] == 23
+
+
+@pytest.mark.parametrize("text", ["", "#"])
+def test_descriptive_edge(text, nlp):
+    doc = nlp(text)
+    assert doc._.token_length
+    assert doc._.sentence_length
+    assert doc._.syllables
+    assert doc._.counts
diff --git a/textdescriptives/tests/test_extractor.py b/textdescriptives/tests/test_extractor.py
new file mode 100644
index 00000000..9e304df7
--- /dev/null
+++ b/textdescriptives/tests/test_extractor.py
@@ -0,0 +1,34 @@
+import textdescriptives as td
+import spacy
+import pytest
+import ftfy
+
+
+@pytest.fixture(scope="function")
+def nlp():
+    nlp = spacy.load("en_core_web_sm")
+    nlp.add_pipe("textdescriptives")
+    return nlp
+
+
+def test_extract_df_single_doc(nlp):
+    doc = nlp("This is just a cute little text. Actually, it's two sentences.")
+    td.extract_df(doc)
+    for metric in ["descriptive_stats", "readability", "dependency_distance"]:
+        td.extract_df(doc, metrics=metric)
+
+
+def test_extract_df_pipe(nlp):
+    text = [
+        "I wonder how well the function works on multiple documents",
+        "Very exciting to see, don't you think?",
+    ]
+    docs = nlp.pipe(text)
+    td.extract_df(docs)
+
+def test_extract_df_subsetters(nlp):
+    doc = nlp("This is just a cute little text. Actually, it's two sentences.")
+    df = td.extract_df(doc, include_text=False)
+    df[td.readability_cols]
+    df[td.dependency_cols]
+    df[td.descriptive_stats_cols]
diff --git a/textdescriptives/tests/test_load_components.py b/textdescriptives/tests/test_load_components.py
new file mode 100644
index 00000000..31c68187
--- /dev/null
+++ b/textdescriptives/tests/test_load_components.py
@@ -0,0 +1,26 @@
+from spacy.lang.en import English
+import pytest
+from textdescriptives import TextDescriptives
+
+
+@pytest.fixture(scope="function")
+def nlp():
+    nlp = English()
+    nlp.add_pipe("textdescriptives")
+    return nlp
+
+
+def test_integration(nlp):
+    assert nlp.pipe_names[-1] == "textdescriptives"
+    for component in [
+        "descriptive_stats",
+        "readability",
+        "dependency_distance",
+        "textdescriptives",
+    ]:
+        assert component in nlp.pipe_names
+
+
+def test_simple(nlp):
+    doc = nlp("This is a short and simple text")
+    assert doc
diff --git a/textdescriptives/tests/test_readability.py b/textdescriptives/tests/test_readability.py
new file mode 100644
index 00000000..638108b3
--- /dev/null
+++ b/textdescriptives/tests/test_readability.py
@@ -0,0 +1,163 @@
+import pytest
+
+from textdescriptives.components import Readability
+from .books import *
+
+from spacy.lang.en import English
+
+import numpy as np
+import ftfy
+
+
+@pytest.fixture(scope="function")
+def nlp():
+    nlp = English()
+    nlp.add_pipe("readability")
+    return nlp
+
+
+def test_readability_integration(nlp):
+    assert "readability" == nlp.pipe_names[-1]
+
+
+def test_readability(nlp):
+    doc = nlp("This is a short and simple sentence")
+    assert doc._.readability
+
+
+@pytest.mark.parametrize("text", ["", "#"])
+def test_readability_edge(text, nlp):
+    doc = nlp(text)
+    for v in doc._.readability.values():
+        v is np.nan
+
+
+@pytest.mark.parametrize(
+    "text,expected",
+    [
+        (oliver_twist, 72.80),
+        (secret_garden, 92.73),
+        (flatland, 68.18),
+        (grade_1, 116.08),
+        (grade_2, 98.18),
+        (grade_3, 101.51),
+        (grade_4, 102.08),
+        (grade_6, 97.96),
+        (grade_8, 91.68),
+        (grade_10, 76.67),
+        (grade_12, 73.72),
+        (grade_14, 65.25),
+    ],
+)
+def test_flesch_reading_ease(text, expected, nlp):
+    text = ftfy.fix_text(text)
+    text = " ".join(text.split())
+    doc = nlp(text)
+    assert pytest.approx(expected, rel=1e-2) == doc._.readability["flesch_reading_ease"]
+
+@pytest.mark.parametrize(
+    "text,expected",
+    [
+        (oliver_twist, 9.48),
+        (secret_garden, 4.04),
+        (flatland, 12.05),
+        (grade_1, -1.65),
+        (grade_2, 1.85),
+        (grade_3, 1.65),
+        (grade_4, 1.20),
+        (grade_6, 2.63),
+        (grade_8, 4.99),
+        (grade_10, 6.75),
+        (grade_12, 6.42),
+        (grade_14, 10.04),
+    ],
+)
+def test_flesch_kincaid_grade(text, expected, nlp):
+    text = ftfy.fix_text(text)
+    text = " ".join(text.split())
+    doc = nlp(text)
+    assert pytest.approx(expected, rel=1e-2) == doc._.readability["flesch_kincaid_grade"]
+
+@pytest.mark.parametrize(
+    "text,expected",
+    [
+        (oliver_twist, 9.47),
+        (secret_garden, 6.63),
+        (flatland, 9.91),
+    ],
+)
+def test_smog(text, expected, nlp):
+    text = ftfy.fix_text(text)
+    text = " ".join(text.split())
+    doc = nlp(text)
+    assert pytest.approx(expected, rel=1e-2) == doc._.readability["smog"]
+
+@pytest.mark.parametrize(
+    "text,expected",
+    [
+        (oliver_twist, 12.19),
+        (secret_garden, 6.98),
+        (flatland, 15.05),
+    ],
+)
+def test_gunning_fog(text, expected, nlp):
+    text = ftfy.fix_text(text)
+    text = " ".join(text.split())
+    doc = nlp(text)
+    assert pytest.approx(expected, rel=1e-2) == doc._.readability["gunning_fog"]
+
+@pytest.mark.parametrize(
+    "text,expected",
+    [
+        (oliver_twist, 11.99),
+        (secret_garden, 5.40),
+        (flatland, 14.98),
+    ],
+)
+def test_automated_readability_index(text, expected, nlp):
+    text = ftfy.fix_text(text)
+    text = " ".join(text.split())
+    doc = nlp(text)
+    assert pytest.approx(expected, rel=1e-2) == doc._.readability["automated_readability_index"]
+
+@pytest.mark.parametrize(
+    "text,expected",
+    [
+        (oliver_twist, 8.75),
+        (secret_garden, 6.39),
+        (flatland, 7.91),
+    ],
+)
+def test_coleman_liau_index(text, expected, nlp):
+    text = ftfy.fix_text(text)
+    text = " ".join(text.split())
+    doc = nlp(text)
+    assert pytest.approx(expected, rel=1e-2) == doc._.readability["coleman_liau_index"]
+
+@pytest.mark.parametrize(
+    "text,expected",
+    [
+        (oliver_twist, 42.70),
+        (secret_garden, 27.07),
+        (flatland, 49.87),
+    ],
+)
+def test_lix(text, expected, nlp):
+    text = ftfy.fix_text(text)
+    text = " ".join(text.split())
+    doc = nlp(text)
+    assert pytest.approx(expected, rel=1e-2) == doc._.readability["lix"]
+
+@pytest.mark.parametrize(
+    "text,expected",
+    [
+        (oliver_twist, 4.37),
+        (secret_garden, 1.81),
+        (flatland, 5.50),
+    ],
+)
+def test_rix(text, expected, nlp):
+    text = ftfy.fix_text(text)
+    text = " ".join(text.split())
+    doc = nlp(text)
+    assert pytest.approx(expected, rel=1e-2) == doc._.readability["rix"]