fix: use powershell for addEnv and addPath

src/utils/env/addEnv.ts

@@ -1,12 +1,12 @@
 import { exportVariable } from "@actions/core"
 import * as core from "@actions/core"
-import execa from "execa"
 import { isGitHubCI } from "./isci"
 import { untildify_user as untildify } from "../path/untildify"
 import { appendFileSync } from "fs"
 import { join } from "path"
 import { isRoot } from "./sudo"
 import { error } from "../io/io"
+import { execPowershell } from "../exec/powershell"
 
 /** An add path function that works locally or inside GitHub Actions */
 export function addEnv(name: string, val: string | undefined) {
@@ -31,11 +31,8 @@ function addEnvSystem(name: string, valGiven: string | undefined) {
   const val = valGiven ?? ""
   switch (process.platform) {
     case "win32": {
-      if (val.length <= 1024) {
-        execa.sync(`setx "${name}" "${val}"`)
-      } else {
-        execa.sync(`powershell -C "[Environment]::SetEnvironmentVariable('${name}', '${val}', 'User')"`)
-      }
+      // We do not use `execa.sync(`setx PATH "${path};%PATH%"`)` because of its character limit
+      execPowershell(`[Environment]::SetEnvironmentVariable('${name}', '${val}', 'User')`)
       core.info(`${name}="${val} was set in the environment."`)
       return
     }

src/utils/exec/powershell.ts

@@ -0,0 +1,19 @@
+import execa from "execa"
+import which from "which"
+
+let powershell: string | undefined
+
+export function execPowershell(command: string) {
+  if (powershell === undefined) {
+    const maybePwsh = which.sync("pwsh", { nothrow: true })
+    if (maybePwsh !== null) {
+      powershell = maybePwsh
+    }
+    const maybePowerShell = which.sync("powershell", { nothrow: true })
+    if (maybePowerShell !== null) {
+      powershell = maybePowerShell
+    }
+  }
+
+  execa.sync(`${powershell} -C "${command}"`)
+}

src/utils/path/addPath.ts

@@ -1,11 +1,11 @@
 import { addPath as ghAddPath } from "@actions/core"
 import { delimiter } from "path"
 import * as core from "@actions/core"
-import execa from "execa"
 import { isGitHubCI } from "../env/isci"
 import { untildify_user as untildify } from "./untildify"
 import { appendFileSync } from "fs"
 import { error } from "../io/io"
+import { execPowershell } from "../exec/powershell"
 
 /** An add path function that works locally or inside GitHub Actions */
 export function addPath(path: string) {
@@ -30,11 +30,10 @@ export function addPath(path: string) {
 function addPathSystem(path: string) {
   switch (process.platform) {
     case "win32": {
-      if (`${path};${process.env.PATH}`.length <= 1024) {
-        execa.sync(`setx PATH "${path};%PATH%"`)
-      } else {
-        execa.sync(`powershell -C "[Environment]::SetEnvironmentVariable('PATH', \\"${path};$env:PATH\\", 'User')"`)
-      }
+      // We do not use `execa.sync(`setx PATH "${path};%PATH%"`)` because of its character limit and also because %PATH% is different for user and system
+      execPowershell(
+        `$USER_PATH=[Environment]::GetEnvironmentVariable('PATH', 'User'); [Environment]::SetEnvironmentVariable('PATH', \\"${path};$USER_PATH\\", 'User')`
+      )
       core.info(`${path} was added to the PATH.`)
       return
     }