[script-on-error] disable for fish shell, and add testscript unit-test

internal/impl/devbox.go

@@ -210,6 +210,17 @@ func (d *Devbox) Shell(ctx context.Context) error {
 	return shell.Run()
 }
 
+// IsUserShellFish returns true if the user's shell is fish.
+// This wrapper function over DevboxShell enables querying from other packages that
+// make a devboxer interface.
+func (d *Devbox) IsUserShellFish() (bool, error) {
+	sh, err := NewDevboxShell(d)
+	if err != nil {
+		return false, err
+	}
+	return sh.IsFish(), nil
+}
+
 func (d *Devbox) RunScript(ctx context.Context, cmdName string, cmdArgs []string) error {
 	ctx, task := trace.NewTask(ctx, "devboxRun")
 	defer task.End()

internal/impl/shell.go

@@ -269,6 +269,12 @@ func (s *DevboxShell) Run() error {
 	return errors.WithStack(err)
 }
 
+// IsFish returns whether this DevboxShell wraps a fish shell. Fish shells are non-posix compatible,
+// and so sometimes we may need to switch logic based on this function's result.
+func (s *DevboxShell) IsFish() bool {
+	return s.name == shFish
+}
+
 func (s *DevboxShell) shellRCOverrides(shellrc string) (extraEnv map[string]string, extraArgs []string) {
 	// Shells have different ways of overriding the shellrc, so we need to
 	// look at the name to know which env vars or args to set when launching the shell.
@@ -319,7 +325,7 @@ func (s *DevboxShell) writeDevboxShellrc() (path string, err error) {
 	}()
 
 	tmpl := shellrcTmpl
-	if s.name == shFish {
+	if s.IsFish() {
 		tmpl = fishrcTmpl
 	}
 

internal/shellgen/scripts.go

@@ -25,6 +25,7 @@ type devboxer interface {
 	Lockfile() *lock.File
 	AllInstallablePackages() ([]*devpkg.Package, error)
 	InstallablePackages() []*devpkg.Package
+	IsUserShellFish() (bool, error)
 	PluginManager() *plugin.Manager
 	ProjectDir() string
 }
@@ -80,8 +81,8 @@ func WriteScriptsToFiles(devbox devboxer) error {
 	return nil
 }
 
-func WriteScriptFile(d devboxer, name string, body string) (err error) {
-	script, err := os.Create(ScriptPath(d.ProjectDir(), name))
+func WriteScriptFile(devbox devboxer, name string, body string) (err error) {
+	script, err := os.Create(ScriptPath(devbox.ProjectDir(), name))
 	if err != nil {
 		return errors.WithStack(err)
 	}
@@ -97,7 +98,17 @@ func WriteScriptFile(d devboxer, name string, body string) (err error) {
 	}
 
 	if featureflag.ScriptExitOnError.Enabled() {
-		body = fmt.Sprintf("set -e\n\n%s", body)
+		// Fish cannot run scripts with `set -e`.
+		// NOTE: Devbox scripts will run using `sh` for consistency. However,
+		// init_hooks in a fish shell will run using `fish` shell, and need this
+		// check.
+		isFish, err := devbox.IsUserShellFish()
+		if err != nil {
+			return errors.WithStack(err)
+		}
+		if !isFish {
+			body = fmt.Sprintf("set -e\n\n%s", body)
+		}
 	}
 	_, err = script.WriteString(body)
 	return errors.WithStack(err)

testscripts/run/script_exit_on_error.test.txt

@@ -0,0 +1,20 @@
+# Testscript to ensure that the script exits on error.
+
+! exec devbox run multi_line
+stdout 'first line'
+! stdout 'second line'
+
+-- devbox.json --
+{
+  "packages": [
+  ],
+  "shell": {
+    "scripts": {
+      "multi_line": [
+        "echo \"first line\"",
+        "exit 1",
+        "echo \"second line\""
+      ]
+    }
+  }
+}