list-ops: reimplement ambiguous tests (exercism#1746)

* Format * Re-implement ambigious test cases * Clarifying comment * Re-add old versions of reimplemented tests * Remove accidantally commited executable * Clarifying commentary about integer division. * Add advice
ee7 · Dec 24, 2020 · bb38e15 · bb38e15
1 parent fcc6028
commit bb38e15
Showing 1 changed file with 120 additions and 0 deletions.
diff --git a/exercises/list-ops/canonical-data.json b/exercises/list-ops/canonical-data.json
@@ -158,6 +158,12 @@
     },
     {
       "description": "folds (reduces) the given list from the left with a function",
+      "comments": [
+        "For function: acc is the accumulator and el is the current element.  ",
+        "The order of the arguments (ie. acc, el or el, acc) should match the ",
+        "conventions common to the language of the track implementing this.   ",
+        "See https://github.com/exercism/problem-specifications/pull/1746#discussion_r548303995 for further advice."
+      ],
       "cases": [
         {
           "uuid": "613b20b7-1873-4070-a3a6-70ae5f50d7cc",
@@ -184,18 +190,78 @@
         {
           "uuid": "d2cf5644-aee1-4dfc-9b88-06896676fe27",
           "description": "direction dependent function applied to non-empty list",
+          "comments": [
+            "Expects integer division (expects / to discard fractions).       "
+          ],
           "property": "foldl",
           "input": {
             "list": [2, 5],
             "initial": 5,
             "function": "(x, y) -> x / y"
           },
           "expected": 0
+        },
+        {
+          "uuid": "36549237-f765-4a4c-bfd9-5d3a8f7b07d2",
+          "reimplements": "613b20b7-1873-4070-a3a6-70ae5f50d7cc",
+          "comments": [
+            "Reimplemented to remove ambiguity about the parameters of the    ",
+            "function input."
+          ],
+          "description": "empty list",
+          "property": "foldl",
+          "input": {
+            "list": [],
+            "initial": 2,
+            "function": "(acc, el) -> el * acc"
+          },
+          "expected": 2
+        },
+        {
+          "uuid": "7a626a3c-03ec-42bc-9840-53f280e13067",
+          "reimplements": "e56df3eb-9405-416a-b13a-aabb4c3b5194",
+          "comments": [
+            "Reimplemented to remove ambiguity about the parameters of the    ",
+            "function input."
+          ],
+          "description": "direction independent function applied to non-empty list",
+          "property": "foldl",
+          "input": {
+            "list": [1, 2, 3, 4],
+            "initial": 5,
+            "function": "(acc, el) -> el + acc"
+          },
+          "expected": 15
+        },
+        {
+          "uuid": "d7fcad99-e88e-40e1-a539-4c519681f390",
+          "reimplements": "d2cf5644-aee1-4dfc-9b88-06896676fe27",
+          "comments": [
+            "Reimplemented to remove ambiguity about the parameters of the    ",
+            "function input. Expects / to preserve fractions. Integer division",
+            "will not work here, since it would compute 1 / 24 = 0. Use the   ",
+            "original test values (d2cf5644-aee1-4dfc-9b88-06896676fe27) if   ",
+            "integer division is expected / required.                         "
+          ],
+          "description": "direction dependent function applied to non-empty list",
+          "property": "foldl",
+          "input": {
+            "list": [1, 2, 3, 4],
+            "initial": 24,
+            "function": "(acc, el) -> el / acc"
+          },
+          "expected": 64
         }
       ]
     },
     {
       "description": "folds (reduces) the given list from the right with a function",
+      "comments": [
+        "For function: acc is the accumulator and el is the current element   ",
+        "The order of the arguments (ie. acc, el or el, acc) should match the ",
+        "conventions common to the language of the track implementing this.   ",
+        "See https://github.com/exercism/problem-specifications/pull/1746#discussion_r548303995 for further advice."
+      ],
       "cases": [
         {
           "uuid": "aeb576b9-118e-4a57-a451-db49fac20fdc",
@@ -222,13 +288,67 @@
         {
           "uuid": "be396a53-c074-4db3-8dd6-f7ed003cce7c",
           "description": "direction dependent function applied to non-empty list",
+          "comments": [
+            "Expects integer division (expects / to discard fractions).       "
+          ],
           "property": "foldr",
           "input": {
             "list": [2, 5],
             "initial": 5,
             "function": "(x, y) -> x / y"
           },
           "expected": 2
+        },
+        {
+          "uuid": "17214edb-20ba-42fc-bda8-000a5ab525b0",
+          "reimplements": "aeb576b9-118e-4a57-a451-db49fac20fdc",
+          "comments": [
+            "Reimplemented to remove ambiguity about the parameters of the    ",
+            "function input."
+          ],
+          "description": "empty list",
+          "property": "foldr",
+          "input": {
+            "list": [],
+            "initial": 2,
+            "function": "(acc, el) -> el * acc"
+          },
+          "expected": 2
+        },
+        {
+          "uuid": "e1c64db7-9253-4a3d-a7c4-5273b9e2a1bd",
+          "reimplements": "c4b64e58-313e-4c47-9c68-7764964efb8e",
+          "comments": [
+            "Reimplemented to remove ambiguity about the parameters of the    ",
+            "function input."
+          ],
+          "description": "direction independent function applied to non-empty list",
+          "property": "foldr",
+          "input": {
+            "list": [1, 2, 3, 4],
+            "initial": 5,
+            "function": "(acc, el) -> el + acc"
+          },
+          "expected": 15
+        },
+        {
+          "uuid": "8066003b-f2ff-437e-9103-66e6df474844",
+          "reimplements": "be396a53-c074-4db3-8dd6-f7ed003cce7c",
+          "comments": [
+            "Reimplemented to remove ambiguity about the parameters of the    ",
+            "function input. Expects / to preserve fractions. Integer division",
+            "will not work here, since it would compute 4 / 24 = 1 / 6. Use   ",
+            "the original test values (be396a53-c074-4db3-8dd6-f7ed003cce7c)  ",
+            "if integer division is expected / required."
+          ],
+          "description": "direction dependent function applied to non-empty list",
+          "property": "foldr",
+          "input": {
+            "list": [1, 2, 3, 4],
+            "initial": 24,
+            "function": "(acc, el) -> el / acc"
+          },
+          "expected": 9
         }
       ]
     },