Add interpolate option

CHANGELOG.rst

@@ -5,8 +5,17 @@ All notable changes to this project will be documented in this file.
 The format is inspired by `Keep a Changelog <https://keepachangelog.com/en/1.0.0/>`_
 and this project adheres to `Semantic Versioning <https://semver.org/spec/v2.0.0.html>`_.
 
-`v0.11.3`_ - 0-Undefined-2023
+`v0.12.0`_ - 0-Undefined-2023
 -----------------------------
+Added
++++++
+- Added support for ``interpolate`` parameter
+  `#495 <https://github.com/joke2k/django-environ/pull/495>`_.
+  This implies a breaking change on the ``interpolate`` parameter.
+  Before this change, ``Env(interpolate=True)`` and ``Env(interpolate=False)`` had the same
+  behaviour. After the change, ``Env(interpolate=False)`` won't substitute values anymore
+  that start with ``$``.
+
 Changed
 +++++++
 - Disabled inline comments handling by default due to potential side effects.
@@ -15,7 +24,6 @@ Changed
   `#499 <https://github.com/joke2k/django-environ/issues/499>`_.
 
 
-
 `v0.11.2`_ - 1-September-2023
 -----------------------------
 Fixed
@@ -399,7 +407,7 @@ Added
 - Initial release.
 
 
-.. _v0.11.3: https://github.com/joke2k/django-environ/compare/v0.11.2...v0.11.3
+.. _v0.12.0: https://github.com/joke2k/django-environ/compare/v0.11.2...v0.12.0
 .. _v0.11.2: https://github.com/joke2k/django-environ/compare/v0.11.1...v0.11.2
 .. _v0.11.1: https://github.com/joke2k/django-environ/compare/v0.11.0...v0.11.1
 .. _v0.11.0: https://github.com/joke2k/django-environ/compare/v0.10.0...v0.11.0
@@ -417,4 +425,4 @@ Added
 .. _v0.4.1: https://github.com/joke2k/django-environ/compare/v0.4...v0.4.1
 .. _v0.4: https://github.com/joke2k/django-environ/compare/v0.3.1...v0.4
 .. _v0.3.1: https://github.com/joke2k/django-environ/compare/v0.3...v0.3.1
-.. _v0.3: https://github.com/joke2k/django-environ/compare/v0.2.1...v0.3
+.. _v0.3: https://github.com/joke2k/django-environ/compare/v0.2.1...v0.3

docs/tips.rst

@@ -290,8 +290,8 @@ The following example demonstrates the above:
 Proxy value
 ===========
 
-Values that being with a ``$`` may be interpolated. Pass ``interpolate=True`` to
-``environ.Env()`` to enable this feature:
+Values that begin with a ``$`` may be interpolated. Pass ``interpolate=True`` to
+``environ.Env()`` to enable this feature (``True`` by default):
 
 .. code-block:: python
 

environ/environ.py

@@ -189,10 +189,11 @@ class Env:
                             for s in ('', 's')]
     CLOUDSQL = 'cloudsql'
 
-    def __init__(self, **scheme):
+    def __init__(self, interpolate=True, **scheme):
         self.smart_cast = True
         self.escape_proxy = False
         self.prefix = ""
+        self.interpolate = interpolate
         self.scheme = scheme
 
     def __call__(self, var, cast=None, default=NOTSET, parse_default=False):
@@ -396,7 +397,8 @@ def get_value(self, var, cast=None, default=NOTSET, parse_default=False):
         # Resolve any proxied values
         prefix = b'$' if isinstance(value, bytes) else '$'
         escape = rb'\$' if isinstance(value, bytes) else r'\$'
-        if hasattr(value, 'startswith') and value.startswith(prefix):
+        if self.interpolate and \
+                hasattr(value, 'startswith') and value.startswith(prefix):
             value = value.lstrip(prefix)
             value = self.get_value(value, cast=cast, default=default)
 

tests/fixtures.py

@@ -65,6 +65,7 @@ def generate_data(cls):
                     BOOL_FALSE_STRING_LIKE_BOOL='False',
                     BOOL_FALSE_BOOL=False,
                     PROXIED_VAR='$STR_VAR',
+                    DOLLAR_VAR_1='SOME_VALUE$S3CR3TK3Y@HELLO',
                     ESCAPED_VAR=r'\$baz',
                     INT_LIST='42,33',
                     INT_TUPLE='(42,33)',

tests/test_env.py

@@ -186,6 +186,17 @@ def test_bool_true(self, value, variable):
     def test_proxied_value(self):
         assert self.env('PROXIED_VAR') == 'bar'
 
+    def test_not_interpolated_proxied_value(self):
+        env = Env(interpolate=False)
+        assert env('PROXIED_VAR') == '$STR_VAR'
+
+    def test_dollar_sign(self):
+        assert self.env('DOLLAR_VAR_1') == 'SOME_VALUE$S3CR3TK3Y@HELLO'
+
+    def test_dollar_sign_not_interpolated(self):
+        env = Env(interpolate=False)
+        assert env('DOLLAR_VAR_1') == 'SOME_VALUE$S3CR3TK3Y@HELLO'
+
     def test_escaped_dollar_sign(self):
         self.env.escape_proxy = True
         assert self.env('ESCAPED_VAR') == '$baz'

tests/test_env.txt

@@ -38,6 +38,9 @@ FLOAT_STRANGE_VAR1=123,420,333.3
 FLOAT_STRANGE_VAR2=123.420.333,3
 FLOAT_NEGATIVE_VAR=-1.0
 PROXIED_VAR=$STR_VAR
+DOLLAR_VAR_1=SOME_VALUE$S3CR3TK3Y@HELLO
+DOLLAR_VAR_2='SOME_VALUE$S3CR3TK3Y@HELLO'
+DOLLAR_VAR_3="SOME_VALUE$S3CR3TK3Y@HELLO"
 ESCAPED_VAR=\$baz
 EMPTY_LIST=
 EMPTY_INT_VAR=