feat: accept Enter as confirmation in confirm()

Previously only "y"/"yes" was accepted. Pressing Enter (empty
input) is the standard UX convention for confirming the default
action, so we now treat it as affirmative. Prompts updated from
[y/n] to [Y/n] to signal the default per convention.

Author: amterp

core/input.go

@@ -21,7 +21,7 @@ func InputConfirm(title string, prompt string) (bool, error) {
 		input.Title(title)
 	}
 	err := input.Run()
-	return strings.HasPrefix(strings.ToLower(response), "y"), err
+	return response == "" || strings.HasPrefix(strings.ToLower(response), "y"), err
 }
 
 func InputText(prompt, hint, default_ string, secret bool) (RadString, error) {

core/shell.go

@@ -136,7 +136,7 @@ func (i *Interpreter) executeShellCmd(shell *rl.Shell) shellResult {
 // warning: as of writing, this is *not* covered in tests
 func realShellExecutor(invocation ShellInvocation) (string, string, int) {
 	if FlagConfirmShellCommands.Value || invocation.IsConfirm {
-		ok, err := InputConfirm(invocation.Command, "Run above command? [y/n] > ")
+		ok, err := InputConfirm(invocation.Command, "Run above command? [Y/n] > ")
 		if err != nil {
 			panic(fmt.Sprintf("Error confirming shell command: %v", err))
 		}

docs-web/docs/examples/brewi.md

@@ -91,7 +91,7 @@ We use [string interpolation](../guide/strings-advanced.md#string-interpolation)
 You can try running the command now! Make sure it's executable (`chmod +x ./brewi`).
 
 Next, we want to ask the user if they'd like to proceed with installing the formula. For that, Rad offers the [`confirm`](../reference/functions.md#confirm) function.
-The default prompt is `Confirm? [y/n] > `, which works fine for us here, so we'll do a simple 0-arg `confirm()` call. The function returns a bool for yes/no, so we'll put it in an if statement.
+The default prompt is `Confirm? [Y/n] > `, which works fine for us here, so we'll do a simple 0-arg `confirm()` call. The function returns a bool for yes/no, so we'll put it in an if statement.
 
 ```rad linenums="1" hl_lines="9-10"
 #!/usr/bin/env rad

docs-web/docs/reference/functions.md

@@ -507,17 +507,18 @@ password = input("Password: ", secret=true)           // -> Hides typed characte
 
 ### confirm
 
-Gets a boolean confirmation from the user (y/n prompt).
+Gets a boolean confirmation from the user (y/n prompt). Accepts "y", "yes", or Enter (empty input) as
+confirmation.
 
 ```rad
-confirm(prompt: str = "Confirm? [y/n] > ") -> bool|error
+confirm(prompt: str = "Confirm? [Y/n] > ") -> bool|error
 ```
 
 ```rad
-if confirm():                        // -> Uses default "Confirm? [y/n] > " prompt
+if confirm():                        // -> Uses default "Confirm? [Y/n] > " prompt
     print("Confirmed!")
 
-if confirm("Delete file? [y/n] "):   // -> Custom prompt
+if confirm("Delete file? [Y/n] "):   // -> Custom prompt
     print("File deleted")
 ```
 

rts/signatures.go

@@ -61,7 +61,7 @@ func init() {
 		newFnSignature(`truncate(_str: str, _len: int) -> error|str`),
 		newFnSignature(`unique(_list: any[]) -> any[]`),
 		newFnSignature(`index_of(_subject: str|list, _target: any, *, n: int = 0, start: int = 0) -> int?`),
-		newFnSignature(`confirm(prompt: str = "Confirm? [y/n] > ") -> error|bool`),
+		newFnSignature(`confirm(prompt: str = "Confirm? [Y/n] > ") -> error|bool`),
 		newFnSignature(`parse_json(_str: str) -> any|error`),
 		newFnSignature(`parse_int(_str: str) -> int|error`),
 		newFnSignature(`parse_float(_str: str) -> float|error`),