sync series tests (#568)

Author: keiravillekode

exercises/practice/series/.meta/example.lua

@@ -1,4 +1,9 @@
 return function(s, length)
+  assert(string.len(s) > 0, "series cannot be empty")
+  assert(length >= 0, "slice length cannot be negative")
+  assert(length > 0, "slice length cannot be zero")
+  assert(length <= string.len(s), "slice length cannot be greater than series length")
+
   return coroutine.wrap(function()
     for i = 1, #s - length + 1 do
       coroutine.yield(s:sub(i, i + length - 1))

exercises/practice/series/.meta/spec_generator.lua

@@ -0,0 +1,35 @@
+local map = function(t, f)
+  local mapped = {}
+  for i, v in ipairs(t) do
+    mapped[i] = f(v)
+  end
+  return mapped
+end
+
+local function render_substrings(substrings)
+  return table.concat(map(substrings, function(substring)
+    return string.format('"%s"', substring)
+  end), ', ')
+end
+
+return {
+  module_name = 'series',
+
+  generate_test = function(case)
+    if case.expected.error then
+      local template = [[
+        assert.has_error(function()
+          series("%s", %s)
+        end, "%s")]]
+      return template:format(case.input.series, case.input.sliceLength, case.expected.error)
+    else
+      local template = [[
+        local result = {}
+        for s in series("%s", %s) do
+          table.insert(result, s)
+        end
+        assert.same({ %s }, result)]]
+      return template:format(case.input.series, case.input.sliceLength, render_substrings(case.expected))
+    end
+  end
+}

exercises/practice/series/.meta/tests.toml

@@ -1,6 +1,13 @@
-# This is an auto-generated file. Regular comments will be removed when this
-# file is regenerated. Regenerating will not touch any manually added keys,
-# so comments can be added in a "comment" key.
+# This is an auto-generated file.
+#
+# Regenerating this file via `configlet sync` will:
+# - Recreate every `description` key/value pair
+# - Recreate every `reimplements` key/value pair, where they exist in problem-specifications
+# - Remove any `include = true` key/value pair (an omitted `include` key implies inclusion)
+# - Preserve any other key/value pair
+#
+# As user-added comments (using the # character) will be removed when this file
+# is regenerated, comments can be added via a `comment` key.
 
 [7ae7a46a-d992-4c2a-9c15-a112d125ebad]
 description = "slices of one from one"
@@ -23,6 +30,9 @@ description = "slices of a long series"
 [6d235d85-46cf-4fae-9955-14b6efef27cd]
 description = "slice length is too large"
 
+[d7957455-346d-4e47-8e4b-87ed1564c6d7]
+description = "slice length is way too large"
+
 [d34004ad-8765-4c09-8ba1-ada8ce776806]
 description = "slice length cannot be zero"
 

exercises/practice/series/series_spec.lua

@@ -1,35 +1,81 @@
 local series = require('series')
 
 describe('series', function()
-  it('should generate 1 character series', function()
+  it('slices of one from one', function()
     local result = {}
-    for s in series('abcde', 1) do
+    for s in series("1", 1) do
       table.insert(result, s)
     end
-    assert.same({ 'a', 'b', 'c', 'd', 'e' }, result)
+    assert.same({ "1" }, result)
   end)
 
-  it('should generate multi-character series', function()
+  it('slices of one from two', function()
     local result = {}
-    for s in series('hello', 3) do
+    for s in series("12", 1) do
       table.insert(result, s)
     end
-    assert.same({ 'hel', 'ell', 'llo' }, result)
+    assert.same({ "1", "2" }, result)
   end)
 
-  it('should generate one series when the series length equals the string length', function()
+  it('slices of two', function()
     local result = {}
-    for s in series('exercism', 8) do
+    for s in series("35", 2) do
       table.insert(result, s)
     end
-    assert.same({ 'exercism' }, result)
+    assert.same({ "35" }, result)
   end)
 
-  it('should return no series when the series length requested is longer than the string', function()
+  it('slices of two overlap', function()
     local result = {}
-    for s in series('1234', 5) do
+    for s in series("9142", 2) do
       table.insert(result, s)
     end
-    assert.same({}, result)
+    assert.same({ "91", "14", "42" }, result)
+  end)
+
+  it('slices can include duplicates', function()
+    local result = {}
+    for s in series("777777", 3) do
+      table.insert(result, s)
+    end
+    assert.same({ "777", "777", "777", "777" }, result)
+  end)
+
+  it('slices of a long series', function()
+    local result = {}
+    for s in series("918493904243", 5) do
+      table.insert(result, s)
+    end
+    assert.same({ "91849", "18493", "84939", "49390", "93904", "39042", "90424", "04243" }, result)
+  end)
+
+  it('slice length is too large', function()
+    assert.has_error(function()
+      series("12345", 6)
+    end, "slice length cannot be greater than series length")
+  end)
+
+  it('slice length is way too large', function()
+    assert.has_error(function()
+      series("12345", 42)
+    end, "slice length cannot be greater than series length")
+  end)
+
+  it('slice length cannot be zero', function()
+    assert.has_error(function()
+      series("12345", 0)
+    end, "slice length cannot be zero")
+  end)
+
+  it('slice length cannot be negative', function()
+    assert.has_error(function()
+      series("123", -1)
+    end, "slice length cannot be negative")
+  end)
+
+  it('empty series is invalid', function()
+    assert.has_error(function()
+      series("", 1)
+    end, "series cannot be empty")
   end)
 end)