Merge #10655 'environ(), getenv(), setenv()'

close #10655

7 files changed, 147 insertions, 8 deletions

diff --git a/runtime/doc/eval.txt b/runtime/doc/eval.txt
index 697e456817..5e8c5151f2 100644
--- a/runtime/doc/eval.txt
+++ b/runtime/doc/eval.txt
@@ -1180,6 +1180,13 @@ $VAR			environment variable
 
 The String value of any environment variable.  When it is not defined, the
 result is an empty string.
+
+The functions `getenv()` and `setenv()` can also be used and work for
+environment variables with non-alphanumeric names.
+The function `environ()` can be used to get a Dict with all environment
+variables.
+
+
 						*expr-env-expand*
 Note that there is a difference between using $VAR directly and using
 expand("$VAR").  Using it directly will only expand environment variables that
@@ -2061,6 +2068,7 @@ did_filetype()			Number	|TRUE| if FileType autocommand event used
 diff_filler({lnum})		Number	diff filler lines about {lnum}
 diff_hlID({lnum}, {col})	Number	diff highlighting at {lnum}/{col}
 empty({expr})			Number	|TRUE| if {expr} is empty
+environ()			Dict	return environment variables
 escape({string}, {chars})	String	escape {chars} in {string} with '\'
 eval({string})			any	evaluate {string} into its value
 eventhandler()			Number	|TRUE| if inside an event handler
@@ -2118,6 +2126,7 @@ getcompletion({pat}, {type} [, {filtered}])
 				List	list of cmdline completion matches
 getcurpos()			List	position of the cursor
 getcwd([{winnr} [, {tabnr}]])	String	get the current working directory
+getenv({name})			String	return environment variable
 getfontname([{name}])		String	name of font being used
 getfperm({fname})		String	file permissions of file {fname}
 getfsize({fname})		Number	size in bytes of file {fname}
@@ -2298,6 +2307,7 @@ setbufline( {expr}, {lnum}, {line})
 setbufvar({expr}, {varname}, {val})	set {varname} in buffer {expr} to {val}
 setcharsearch({dict})		Dict	set character search from {dict}
 setcmdpos({pos})		Number	set cursor position in command-line
+setenv({name}, {val})		none	set environment variable
 setfperm({fname}, {mode}	Number	set {fname} file permissions to {mode}
 setline({lnum}, {line})		Number	set line {lnum} to {line}
 setloclist({nr}, {list}[, {action}[, {what}]])
@@ -3344,6 +3354,14 @@ diff_hlID({lnum}, {col})				*diff_hlID()*
 		The highlight ID can be used with |synIDattr()| to obtain
 		syntax information about the highlighting.
 
+environ()						*environ()*
+		Return all of environment variables as dictionary. You can
+		check if an environment variable exists like this: >
+			:echo has_key(environ(), 'HOME')
+<		Note that the variable name may be CamelCase; to ignore case
+		use this: >
+			:echo index(keys(environ()), 'HOME', 0, 1) != -1
+
 empty({expr})						*empty()*
 		Return the Number 1 if {expr} is empty, zero otherwise.
 		A |List| or |Dictionary| is empty when it does not have any
@@ -4333,14 +4351,11 @@ getcwd([{winnr}[, {tabnr}]])				*getcwd()*
 <		If {winnr} is -1 it is ignored, only the tab is resolved.
 		{winnr} can be the window number or the |window-ID|.
 
-
-getfsize({fname})					*getfsize()*
-		The result is a Number, which is the size in bytes of the
-		given file {fname}.
-		If {fname} is a directory, 0 is returned.
-		If the file {fname} can't be found, -1 is returned.
-		If the size of {fname} is too big to fit in a Number then -2
-		is returned.
+getenv({name})						*getenv()*
+		Return the value of environment variable {name}.
+		When the variable does not exist |v:null| is returned.  That
+		is different from a variable set to an empty string.
+		See also |expr-env|.
 
 getfontname([{name}])					*getfontname()*
 		Without an argument returns the name of the normal font being
@@ -4371,6 +4386,14 @@ getfperm({fname})					*getfperm()*
 
 		For setting permissions use |setfperm()|.
 
+getfsize({fname})					*getfsize()*
+		The result is a Number, which is the size in bytes of the
+		given file {fname}.
+		If {fname} is a directory, 0 is returned.
+		If the file {fname} can't be found, -1 is returned.
+		If the size of {fname} is too big to fit in a Number then -2
+		is returned.
+
 getftime({fname})					*getftime()*
 		The result is a Number, which is the last modification time of
 		the given file {fname}.  The value is measured as seconds
@@ -7079,6 +7102,11 @@ setcmdpos({pos})					*setcmdpos()*
 		Returns 0 when successful, 1 when not editing the command
 		line.
 
+setenv({name}, {val})						*setenv()*
+		Set environment variable {name} to {val}.
+		When {val} is |v:null| the environment variable is deleted.
+		See also |expr-env|.
+
 setfperm({fname}, {mode})				*setfperm()* *chmod*
 		Set the file permissions for {fname} to {mode}.
 		{mode} must be a string with 9 characters.  It is of the form
diff --git a/runtime/doc/usr_41.txt b/runtime/doc/usr_41.txt
index c806507c3e..b26b7cb646 100644
--- a/runtime/doc/usr_41.txt
+++ b/runtime/doc/usr_41.txt
@@ -770,6 +770,9 @@ System functions and manipulation of files:
 	rename()		rename a file
 	system()		get the result of a shell command as a string
 	systemlist()		get the result of a shell command as a list
+	environ()		get all environment variables
+	getenv()		get one environment variable
+	setenv()		set an environment variable
 	hostname()		name of the system
 	readfile()		read a file into a List of lines
 	readdir()		get a List of file names in a directory
@@ -899,6 +902,7 @@ GUI:						*gui-functions*
 	getwinposy()		Y position of the Vim window
 	balloon_show()		set the balloon content
 	balloon_split()		split a message for a balloon
+	balloon_gettext()	get the text in the balloon
 
 Vim server:					*server-functions*
 	serverlist()		return the list of server names
diff --git a/src/nvim/eval.c b/src/nvim/eval.c
index d82a081c27..7ffa59f298 100644
--- a/src/nvim/eval.c
+++ b/src/nvim/eval.c
@@ -8495,6 +8495,25 @@ static void f_empty(typval_T *argvars, typval_T *rettv, FunPtr fptr)
   rettv->vval.v_number = n;
 }
 
+/// "environ()" function
+static void f_environ(typval_T *argvars, typval_T *rettv, FunPtr fptr)
+{
+  tv_dict_alloc_ret(rettv);
+
+  for (int i = 0; ; i++) {
+    // TODO(justinmk): use os_copyfullenv from #7202 ?
+    char *envname = os_getenvname_at_index((size_t)i);
+    if (envname == NULL) {
+      break;
+    }
+    const char *value = os_getenv(envname);
+    tv_dict_add_str(rettv->vval.v_dict,
+                    (char *)envname, STRLEN((char *)envname),
+                    value == NULL ? "" : value);
+    xfree(envname);
+  }
+}
+
 /*
  * "escape({string}, {chars})" function
  */
@@ -8508,6 +8527,20 @@ static void f_escape(typval_T *argvars, typval_T *rettv, FunPtr fptr)
   rettv->v_type = VAR_STRING;
 }
 
+/// "getenv()" function
+static void f_getenv(typval_T *argvars, typval_T *rettv, FunPtr fptr)
+{
+  char_u *p = (char_u *)vim_getenv(tv_get_string(&argvars[0]));
+
+  if (p == NULL) {
+    rettv->v_type = VAR_SPECIAL;
+    rettv->vval.v_number = kSpecialVarNull;
+    return;
+  }
+  rettv->vval.v_string = p;
+  rettv->v_type = VAR_STRING;
+}
+
 /*
  * "eval()" function
  */
@@ -15319,6 +15352,20 @@ static void f_setcmdpos(typval_T *argvars, typval_T *rettv, FunPtr fptr)
   }
 }
 
+/// "setenv()" function
+static void f_setenv(typval_T *argvars, typval_T *rettv, FunPtr fptr)
+{
+  char namebuf[NUMBUFLEN];
+  char valbuf[NUMBUFLEN];
+  const char *name = tv_get_string_buf(&argvars[0], namebuf);
+
+  if (argvars[1].v_type == VAR_SPECIAL
+      && argvars[1].vval.v_number == kSpecialVarNull) {
+    os_unsetenv(name);
+  } else {
+    vim_setenv(name, tv_get_string_buf(&argvars[1], valbuf));
+  }
+}
 
 /// "setfperm({fname}, {mode})" function
 static void f_setfperm(typval_T *argvars, typval_T *rettv, FunPtr fptr)
diff --git a/src/nvim/eval.lua b/src/nvim/eval.lua
index 0b77a24f7a..db45409e77 100644
--- a/src/nvim/eval.lua
+++ b/src/nvim/eval.lua
@@ -89,6 +89,7 @@ return {
     diff_filler={args=1},
     diff_hlID={args=2},
     empty={args=1},
+    environ={},
     escape={args=2},
     eval={args=1},
     eventhandler={},
@@ -135,6 +136,7 @@ return {
     getcompletion={args={2, 3}},
     getcurpos={},
     getcwd={args={0,2}},
+    getenv={args={1}},
     getfontname={args={0, 1}},
     getfperm={args=1},
     getfsize={args=1},
@@ -274,6 +276,7 @@ return {
     setbufvar={args=3},
     setcharsearch={args=1},
     setcmdpos={args=1},
+    setenv={args=2},
     setfperm={args=2},
     setline={args=2},
     setloclist={args={2, 4}},
diff --git a/src/nvim/os/env.c b/src/nvim/os/env.c
index 2278c325ea..bef78d8cc8 100644
--- a/src/nvim/os/env.c
+++ b/src/nvim/os/env.c
@@ -45,6 +45,7 @@ void env_init(void)
 }
 
 /// Like getenv(), but returns NULL if the variable is empty.
+/// @see os_env_exists
 const char *os_getenv(const char *name)
   FUNC_ATTR_NONNULL_ALL
 {
diff --git a/src/nvim/testdir/test_environ.vim b/src/nvim/testdir/test_environ.vim
new file mode 100644
index 0000000000..094c4ce36f
--- /dev/null
+++ b/src/nvim/testdir/test_environ.vim
@@ -0,0 +1,44 @@
+scriptencoding utf-8
+
+func Test_environ()
+  unlet! $TESTENV
+  call assert_equal(0, has_key(environ(), 'TESTENV'))
+  let $TESTENV = 'foo'
+  call assert_equal(1, has_key(environ(), 'TESTENV'))
+  let $TESTENV = 'こんにちわ'
+  call assert_equal('こんにちわ', environ()['TESTENV'])
+endfunc
+
+func Test_getenv()
+  unlet! $TESTENV
+  call assert_equal(v:null, getenv('TESTENV'))
+  let $TESTENV = 'foo'
+  call assert_equal('foo', getenv('TESTENV'))
+endfunc
+
+func Test_setenv()
+  unlet! $TESTENV
+  call setenv('TEST ENV', 'foo')
+  call assert_equal('foo', getenv('TEST ENV'))
+  call setenv('TEST ENV', v:null)
+  call assert_equal(v:null, getenv('TEST ENV'))
+endfunc
+
+func Test_external_env()
+  call setenv('FOO', 'HelloWorld')
+  if has('win32')
+    let result = system('echo %FOO%')
+  else
+    let result = system('echo $FOO')
+  endif
+  let result = substitute(result, '[ \r\n]', '', 'g')
+  call assert_equal('HelloWorld', result)
+
+  call setenv('FOO', v:null)
+  if has('win32')
+    let result = system('set | grep ^FOO=')
+  else
+    let result = system('env | grep ^FOO=')
+  endif
+  call assert_equal('', result)
+endfunc
diff --git a/test/functional/eval/environ_spec.lua b/test/functional/eval/environ_spec.lua
new file mode 100644
index 0000000000..eb52f9e2da
--- /dev/null
+++ b/test/functional/eval/environ_spec.lua
@@ -0,0 +1,12 @@
+local helpers = require('test.functional.helpers')(after_each)
+local clear = helpers.clear
+local eq = helpers.eq
+local environ = helpers.funcs.environ
+
+describe('environ()', function()
+  it('handles empty env variable', function()
+    clear({env={EMPTY_VAR=""}})
+    eq("", environ()['EMPTY_VAR'])
+    eq(nil, environ()['DOES_NOT_EXIST'])
+  end)
+end)