Move hardcoded exclusions from the generator script to the spec_generator module (#119)

Author: glennj

CONTRIBUTING.md

@@ -56,6 +56,8 @@
 
    If there are, add `include = false` properties in the exercise's `.meta/tests.toml` file.
 
+   If there are whole test groups to exclude, add an "exclusions" property to the spec_generator module (see below).
+
 1. Considering the canonical data, decide if this exercise makes sense to use a test generator.
 
     - If no:
@@ -76,6 +78,8 @@
                 - `case` is the Lua object for the test case
                 - `level`, default value 2, is the indentation level of the body.
             - (optional) `test_helpers`: (string) a block of code that gets added at the top of the top-level `describe` block.
+            - (optional) `exclusions`: (list of tables) identifies things from the canonical data to exclude.
+                - See `simple-linked-list` and `gigasecond` spec generators for examples.
 
             Look to see how it's implemented for other exercises.
             The `space-age` one is interesting: it uses the test_helpers block to register a custom assertion, and has expected errors.

bin/generate-spec

@@ -48,7 +48,7 @@ included_tests_from_toml = (path) ->
 
 -- ----------------------------------------------------------
 -- functions marked as global so spec_generators can see them
-export indent, quote, is_json_null, is_empty
+export indent, quote, is_json_null, is_empty, contains
 
 indent = (text, level) -> string.rep('  ', level) .. text
 
@@ -63,15 +63,25 @@ is_empty = (t) -> not next t
 -- the dkjson `json.null` value is an empty table
 is_json_null = (value) -> type(value) == 'table' and is_empty(value)
 
+-- a table contains a value
+contains = (t, v) ->
+  for elem in *t
+    return true if elem == v
+  false
+
 -- ----------------------------------------------------------
 
 
 test_cmd = 'it'
 
 process = (node, level=0) ->
-  if exercise_name == 'simple-linked-list' and node.description == 'toList LIFO'
-    -- skip this whole node
-    return ''
+  -- exclude the test cases in this node?
+  for exclusion in *(spec_generator.exclusions or {})
+    if node[exclusion.key]
+      if exclusion.op == 'contains'
+        return '' if contains node[exclusion.key], exclusion.value
+      else
+        return '' if node[exclusion.key] == exclusion.value
 
   if node.cases
     output = {}

exercises/practice/simple-linked-list/.meta/spec_generator.moon

@@ -31,4 +31,8 @@ int_list = (list) -> "{#{table.concat list, ', '}}"
         table.insert lines, "assert.are.same #{int_list op.expected}, result"
 
     table.concat [indent line, level for line in *lines], '\n'
+
+  exclusions: {
+    {key: 'description', value: 'toList LIFO'}
+  }
 }