cleanup environment variable handling + unit tests

  * removed a putenv() implementation which isn't needed anymore
  * mch_getenv() and mch_setenv() are now functions in src/os/env.c
  * removes direct calls to getenv() and setenv() outside of src/os/env.c
  * refactored the logic of get_env_name into mch_getenvname_at_index
  * added unittests for the functions in os/env.c

1 files changed, 95 insertions, 0 deletions

diff --git a/test/unit/os/env.moon b/test/unit/os/env.moon
new file mode 100644
index 0000000000..b83fcac5f1
--- /dev/null
+++ b/test/unit/os/env.moon
@@ -0,0 +1,95 @@
+{:cimport, :internalize, :eq, :ffi, :lib, :cstr} = require 'test.unit.helpers'
+require 'lfs'
+
+-- fs = cimport './src/os/os.h'
+-- remove these statements once 'cimport' is working properly for misc1.h
+env = lib
+ffi.cdef [[
+const char *mch_getenv(const char *name);
+int mch_setenv(const char *name, const char *value, int override);
+char *mch_getenvname_at_index(size_t index);
+]]
+
+str_to_charp = (str) ->
+  cstr (string.len str), str
+
+NULL = ffi.cast 'void*', 0
+
+describe 'env function', ->
+
+  mch_setenv = (name, value, override) ->
+    env.mch_setenv (str_to_charp name), (str_to_charp value), override
+
+  mch_getenv = (name) ->
+    rval = env.mch_getenv (str_to_charp name)
+    if rval != NULL
+      ffi.string rval
+    else
+      NULL
+
+  describe 'mch_setenv', ->
+
+    OK = 0
+
+    it 'sets an env variable and returns OK', ->
+      name = 'NEOVIM_UNIT_TEST_SETENV_1N'
+      value = 'NEOVIM_UNIT_TEST_SETENV_1V'
+      eq nil, os.getenv name
+      eq OK, (mch_setenv name, value, 1)
+      eq value, os.getenv name
+
+    it "dosn't overwrite an env variable if overwrite is 0", ->
+      name = 'NEOVIM_UNIT_TEST_SETENV_2N'
+      value = 'NEOVIM_UNIT_TEST_SETENV_2V'
+      value_updated = 'NEOVIM_UNIT_TEST_SETENV_2V_UPDATED'
+      eq OK, (mch_setenv name, value, 0)
+      eq value, os.getenv name
+      eq OK, (mch_setenv name, value_updated, 0)
+      eq value, os.getenv name
+
+  describe 'mch_getenv', ->
+
+    it 'reads an env variable', ->
+      name = 'NEOVIM_UNIT_TEST_GETENV_1N'
+      value =  'NEOVIM_UNIT_TEST_GETENV_1V'
+      eq NULL, mch_getenv name
+      -- need to use mch_setenv, because lua dosn't have a setenv function
+      mch_setenv name, value, 1
+      eq value, mch_getenv name
+
+    it 'returns NULL if the env variable is not found', ->
+      name = 'NEOVIM_UNIT_TEST_GETENV_NOTFOUND'
+      eq NULL, mch_getenv name
+
+  describe 'mch_getenvname_at_index', ->
+
+    it 'returns names of environment variables', ->
+      test_name = 'NEOVIM_UNIT_TEST_GETENVNAME_AT_INDEX_1N'
+      test_value =  'NEOVIM_UNIT_TEST_GETENVNAME_AT_INDEX_1V'
+      mch_setenv test_name, test_value, 1
+      i = 0
+      names = {}
+      found_name = false
+      name = env.mch_getenvname_at_index i
+      while name != NULL
+        table.insert names, ffi.string name
+        if (ffi.string name) == test_name
+          found_name = true
+        i += 1
+        name = env.mch_getenvname_at_index i
+
+      eq true, (table.getn names) > 0
+      eq true, found_name
+
+    it 'returns NULL if the index is out of bounds', ->
+      huge = ffi.new 'size_t', 10000
+      maxuint32 = ffi.new 'size_t', 4294967295
+      eq NULL, env.mch_getenvname_at_index huge
+      eq NULL, env.mch_getenvname_at_index maxuint32
+      if ffi.abi '64bit'
+        -- couldn't use a bigger number because it gets converted to 
+        -- double somewere, should be big enough anyway
+        -- maxuint64 = ffi.new 'size_t', 18446744073709551615
+        maxuint64 = ffi.new 'size_t', 18446744073709000000
+        eq NULL, env.mch_getenvname_at_index maxuint64
+