js -d:nodejs now supports osenv: getEnv, putEnv, envPairs, delEnv, existsEnv (v2) (#15826)

* js -d:nodejs now supports osenv: `getEnv`, `putEnv`, `envPairs`, `delEnv`, `existsEnv`

* refactor to osenv

* fix for js (without -d:nodejs) + VM

Co-authored-by: Andreas Rumpf <rumpf_a@web.de>

changelog.md

@@ -31,6 +31,8 @@
 - Removed deprecated `iup` module from stdlib, it has already moved to
   [nimble](https://github.com/nim-lang/iup).
 
+- Removed deprecated `iup` module from stdlib, it has already moved to [nimble](https://github.com/nim-lang/iup).
+- nodejs now supports osenv: `getEnv`, `putEnv`, `envPairs`, `delEnv`, `existsEnv`
 - `doAssertRaises` now correctly handles foreign exceptions.
 
 ## Language changes

lib/pure/includes/osenv.nim

@@ -3,29 +3,65 @@
 when not declared(os) and not declared(ospaths):
   {.error: "This is an include file for os.nim!".}
 
-when defined(windows):
+when defined(nodejs):
+  proc getEnv*(key: string, default = ""): TaintedString {.tags: [ReadEnvEffect].} =
+    var ret: cstring
+    let key2 = key.cstring
+    {.emit: "`ret` = process.env[`key2`];".}
+    result = $ret
+
+  proc existsEnv*(key: string): bool {.tags: [ReadEnvEffect].} =
+    var key2 = key.cstring
+    var ret: bool
+    {.emit: "`ret` = `key2` in process.env;".}
+    result = ret
+
+  proc putEnv*(key, val: string) {.tags: [WriteEnvEffect].} =
+    var key2 = key.cstring
+    var val2 = val.cstring
+    {.emit: "process.env[`key2`] = `val2`;".}
+
+  proc delEnv*(key: string) {.tags: [WriteEnvEffect].} =
+    var key2 = key.cstring
+    {.emit: "delete process.env[`key2`];".}
+
+  iterator envPairs*(): tuple[key, value: TaintedString] {.tags: [ReadEnvEffect].} =
+    var num: int
+    var keys: RootObj
+    {.emit: "`keys` = Object.keys(process.env); `num` = `keys`.length;".}
+    for i in 0..<num:
+      var key, value: cstring
+      {.emit: "`key` = `keys`[`i`]; `value` = process.env[`key`];".}
+      yield ($key, $value)
+
+# commented because it must keep working with js+VM
+# elif defined(js):
+#   {.error: "requires -d:nodejs".}
+
+else:
+  when defined(windows):
     from parseutils import skipIgnoreCase
 
-proc c_getenv(env: cstring): cstring {.
+  proc c_getenv(env: cstring): cstring {.
     importc: "getenv", header: "<stdlib.h>".}
-proc c_putenv(env: cstring): cint {.
+  proc c_putenv(env: cstring): cint {.
     importc: "putenv", header: "<stdlib.h>".}
-proc c_unsetenv(env: cstring): cint {.
+  proc c_unsetenv(env: cstring): cint {.
     importc: "unsetenv", header: "<stdlib.h>".}
 
-# Environment handling cannot be put into RTL, because the ``envPairs``
+  # Environment handling cannot be put into RTL, because the ``envPairs``
-# iterator depends on ``environment``.
+  # iterator depends on ``environment``.
 
-var
+  var
     envComputed {.threadvar.}: bool
     environment {.threadvar.}: seq[string]
 
-when defined(nimV2):
+  when defined(nimV2):
     proc unpairedEnvAllocs*(): int =
       result = environment.len
       if result > 0: inc result
 
-when defined(windows) and not defined(nimscript):
+  when defined(windows) and not defined(nimscript):
     # because we support Windows GUI applications, things get really
     # messy here...
     when useWinUnicode:
@@ -66,7 +102,7 @@ when defined(windows) and not defined(nimscript):
           discard freeEnvironmentStringsA(env)
         envComputed = true
 
-else:
+  else:
     const
       useNSGetEnviron = (defined(macosx) and not defined(ios) and not defined(emscripten)) or defined(nimscript)
 
@@ -98,7 +134,7 @@ else:
           inc(i)
         envComputed = true
 
-proc findEnvVar(key: string): int =
+  proc findEnvVar(key: string): int =
     getEnvVarsC()
     var temp = key & '='
     for i in 0..high(environment):
@@ -108,7 +144,7 @@ proc findEnvVar(key: string): int =
         if startsWith(environment[i], temp): return i
     return -1
 
-proc getEnv*(key: string, default = ""): TaintedString {.tags: [ReadEnvEffect].} =
+  proc getEnv*(key: string, default = ""): TaintedString {.tags: [ReadEnvEffect].} =
     ## Returns the value of the `environment variable`:idx: named `key`.
     ##
     ## If the variable does not exist, `""` is returned. To distinguish
@@ -135,7 +171,7 @@ proc getEnv*(key: string, default = ""): TaintedString {.tags: [ReadEnvEffect].}
         if env == nil: return TaintedString(default)
         result = TaintedString($env)
 
-proc existsEnv*(key: string): bool {.tags: [ReadEnvEffect].} =
+  proc existsEnv*(key: string): bool {.tags: [ReadEnvEffect].} =
     ## Checks whether the environment variable named `key` exists.
     ## Returns true if it exists, false otherwise.
     ##
@@ -153,7 +189,7 @@ proc existsEnv*(key: string): bool {.tags: [ReadEnvEffect].} =
       if c_getenv(key) != nil: return true
       else: return findEnvVar(key) >= 0
 
-proc putEnv*(key, val: string) {.tags: [WriteEnvEffect].} =
+  proc putEnv*(key, val: string) {.tags: [WriteEnvEffect].} =
     ## Sets the value of the `environment variable`:idx: named `key` to `val`.
     ## If an error occurs, `OSError` is raised.
     ##
@@ -187,7 +223,7 @@ proc putEnv*(key, val: string) {.tags: [WriteEnvEffect].} =
         if c_putenv(environment[indx]) != 0'i32:
           raiseOSError(osLastError())
 
-proc delEnv*(key: string) {.tags: [WriteEnvEffect].} =
+  proc delEnv*(key: string) {.tags: [WriteEnvEffect].} =
     ## Deletes the `environment variable`:idx: named `key`.
     ## If an error occurs, `OSError` is raised.
     ##
@@ -212,7 +248,7 @@ proc delEnv*(key: string) {.tags: [WriteEnvEffect].} =
           raiseOSError(osLastError())
       environment.delete(indx)
 
-iterator envPairs*(): tuple[key, value: TaintedString] {.tags: [ReadEnvEffect].} =
+  iterator envPairs*(): tuple[key, value: TaintedString] {.tags: [ReadEnvEffect].} =
     ## Iterate over all `environments variables`:idx:.
     ##
     ## In the first component of the tuple is the name of the current variable stored,

tests/js/tos.nim

@@ -19,3 +19,29 @@ block:
   if not isWindows:
     doAssert cwd.isAbsolute
     doAssert relativePath(getCurrentDir() / "foo", "bar") == "../foo"
+
+import std/sequtils
+
+template main =
+  putEnv("foo", "bar")
+  doAssert getEnv("foo") == "bar"
+  doAssert existsEnv("foo")
+
+  putEnv("foo", "")
+  doAssert existsEnv("foo")
+  putEnv("foo", "bar2")
+  doAssert getEnv("foo") == "bar2"
+
+  when nimvm:
+    discard
+  else:
+    # need support in vmops: envPairs, delEnv
+    let s = toSeq(envPairs())
+    doAssert ("foo", "bar2") in s
+    doAssert ("foo", "bar") notin s
+
+    delEnv("foo")
+    doAssert not existsEnv("foo")
+
+static: main()
+main()