Add first part of test framework: parse tests.

tester.lua

@@ -0,0 +1,76 @@
+--- Shallow table copy
+local function cp(t)
+  local t1 = {}
+  for k,v in pairs(t) do t1[k]=v end
+  return t1
+end
+
+--- Path tokenizer, builds a table t for which t.token=true
+-- @param fn string containing a filename (fullpath)
+-- @return table for which keys token = true
+local function tags_from_path(fn)
+  local tags = {}
+  for token in fn:gmatch("[^\\/]+") do
+    local token_lua = token:match("(.*)%.lua$")
+    tags[token_lua or token] = true
+  end
+  return tags
+end
+
+--- Parser for the tests.
+-- @param fn string containing a filename (fullpath)
+-- @return array containing test specs (name, code, description, tags)
+-- @return lookup table for tests
+-- @return prelude table containing prelude code, description and tags.
+local function parse_test(fn)
+  local tests = {}
+  local lookup_tests = {}
+  local prelude = {
+    description = {},
+    code = {},
+    tags = tags_from_path(fn),
+  }
+  local current_test = prelude
+  local function store_test()
+    if current_test and current_test~=prelude then 
+      current_test.code = table.concat(current_test.code,"\n")
+      current_test.description = table.concat(current_test.description,"\n")
+      tests[#tests+1] = current_test
+      lookup_tests[current_test.name] = #tests
+    end
+  end
+  for line in io.lines(fn) do
+    if line:match("^%-%-%-") then
+      -- Next test is reached
+      store_test()
+      local testname = line:match("^%-%-%-%s*(.*)$")
+      if lookup_tests[testname] then
+        error("Test "..testname.." is defined twice in the same file. Please give the tests unique names.")
+      end
+      -- Add current test to the tests table and start new current test table.
+      current_test = {
+        name = testname,
+        description = cp(prelude.description),
+        tags = cp(prelude.tags),
+        code = cp(prelude.code),
+      }
+    elseif line:match("^%-%-") and #current_test.code==#prelude.code then
+    -- Continue building current test description (and possibly tags)
+      current_test.description[#current_test.description+1] = line:match("^%-%-%s*(.*)$")
+      for tag in line:gmatch("%+([A-Za-z_][A-Za-z0-9_]*)") do
+        current_test.tags[tag] = true
+      end
+    else 
+      current_test.code[#current_test.code+1] = line
+    end
+  end
+  store_test()
+  prelude.code = table.concat(prelude.code,"\n")
+  prelude.description = table.concat(prelude.description,"\n")
+  return tests, lookup_tests, prelude
+end
+
+
+return {
+  parse = parse_test
+}