Merge pull request microsoft#185355 from microsoft/merogge/fish-s

respect `fish_prompt`, re-enable automatic fish shell integration

Author: meganrogge

src/vs/platform/terminal/node/terminalEnvironment.ts

@@ -176,12 +176,11 @@ export function getShellIntegrationInjection(
 		case 'fish': {
 			// The injection mechanism used for fish is to add a custom dir to $XDG_DATA_DIRS which
 			// is similar to $ZDOTDIR in zsh but contains a list of directories to run from.
-			// const oldDataDirs = env?.XDG_DATA_DIRS ?? '/usr/local/share:/usr/share';
-			// const newDataDir = path.join(appRoot, 'out/vs/workbench/contrib/terminal/browser/media/fish_xdg_data');
-			// envMixin['XDG_DATA_DIRS'] = `${oldDataDirs}:${newDataDir}`;
-			// addEnvMixinPathPrefix(options, envMixin);
-			// return { newArgs: undefined, envMixin };
-			return undefined;
+			const oldDataDirs = env?.XDG_DATA_DIRS ?? '/usr/local/share:/usr/share';
+			const newDataDir = path.join(appRoot, 'out/vs/workbench/contrib/terminal/browser/media/fish_xdg_data');
+			envMixin['XDG_DATA_DIRS'] = `${oldDataDirs}:${newDataDir}`;
+			addEnvMixinPathPrefix(options, envMixin);
+			return { newArgs: undefined, envMixin };
 		}
 		case 'pwsh': {
 			if (!originalArgs || arePwshImpliedArgs(originalArgs)) {

src/vs/workbench/contrib/terminal/browser/media/fish_xdg_data/fish/vendor_conf.d/shellIntegration.fish

@@ -98,6 +98,32 @@ function __vsc_cmd_clear --on-event fish_cancel
 	__vsc_esc D
 end
 
+# Preserve the user's existing prompt, to wrap in our escape sequences.
+function __preserve_fish_prompt --on-event fish_prompt
+	if functions --query fish_prompt
+		if functions --query __vsc_fish_prompt
+			# Erase the fallback so it can be set to the user's prompt
+			functions --erase __vsc_fish_prompt
+		end
+		functions --copy fish_prompt __vsc_fish_prompt
+		functions --erase __preserve_fish_prompt
+		# Now __vsc_fish_prompt is guaranteed to be defined
+		__init_vscode_shell_integration
+	else
+		if functions --query __vsc_fish_prompt
+			functions --erase __preserve_fish_prompt
+			__init_vscode_shell_integration
+		else
+			# There is no fish_prompt set, so stick with the default
+			# Now __vsc_fish_prompt is guaranteed to be defined
+			function __vsc_fish_prompt
+				echo -n (whoami)@(prompt_hostname) (prompt_pwd) '~> '
+			end
+		end
+	end
+end
+__preserve_fish_prompt
+
 # Sent whenever a new fish prompt is about to be displayed.
 # Updates the current working directory.
 function __vsc_update_cwd --on-event fish_prompt
@@ -128,29 +154,28 @@ function __vsc_fish_has_mode_prompt -d "Returns true if fish_mode_prompt is defi
 	functions fish_mode_prompt | string match -rvq '^ *(#|function |end$|$)'
 end
 
-# Preserve the user's existing prompt, to wrap in our escape sequences.
-functions --copy fish_prompt __vsc_fish_prompt
-
 # Preserve and wrap fish_mode_prompt (which appears to the left of the regular
 # prompt), but only if it's not defined as an empty function (which is the
 # officially documented way to disable that feature).
-if __vsc_fish_has_mode_prompt
-	functions --copy fish_mode_prompt __vsc_fish_mode_prompt
-
-	function fish_mode_prompt
-		__vsc_fish_prompt_start
-		__vsc_fish_mode_prompt
-	end
-
-	function fish_prompt
-		__vsc_fish_prompt
-		__vsc_fish_cmd_start
-	end
-else
-	# No fish_mode_prompt, so put everything in fish_prompt.
-	function fish_prompt
-		__vsc_fish_prompt_start
-		__vsc_fish_prompt
-		__vsc_fish_cmd_start
+function __init_vscode_shell_integration
+	if __vsc_fish_has_mode_prompt
+		functions --copy fish_mode_prompt __vsc_fish_mode_prompt
+
+		function fish_mode_prompt
+			__vsc_fish_prompt_start
+			__vsc_fish_mode_prompt
+		end
+
+		function fish_prompt
+			__vsc_fish_prompt
+			__vsc_fish_cmd_start
+		end
+	else
+		# No fish_mode_prompt, so put everything in fish_prompt.
+		function fish_prompt
+			__vsc_fish_prompt_start
+			__vsc_fish_prompt
+			__vsc_fish_cmd_start
+		end
 	end
 end