feat: pass attempt number, max to cmd in env var

.gitignore

@@ -7,6 +7,7 @@
 
 /help
 /recur
+/test/env
 /test/exit99
 /test/hello
 /test/sleep

Makefile

@@ -1,4 +1,4 @@
-TEST_BINARIES := test/exit99 test/hello test/sleep
+TEST_BINARIES := test/env test/exit99 test/hello test/sleep
 
 .PHONY: all
 all: README.md recur
@@ -21,6 +21,9 @@ release:
 test: recur $(TEST_BINARIES)
 	go test
 
+test/env: test/env.go
+	go build -o $@ test/env.go
+
 test/exit99: test/exit99.go
 	go build -o $@ test/exit99.go
 

README.md

@@ -92,6 +92,10 @@ recur exits with the last command's exit code unless the user overrides this in
 When the command is not found during the last attempt,
 recur exits with the code 255.
 
+recur sets the environment variable `RECUR_ATTEMPT` for the command it runs to the current attempt number.
+This way the command can access the attempt counter.
+recur also sets `RECUR_MAX_ATTEMPTS` to the value of `-a`/`--attempts`.
+
 ## Conditions
 
 recur supports a limited form of scripting.

README.template.md

@@ -47,6 +47,10 @@ recur exits with the last command's exit code unless the user overrides this in
 When the command is not found during the last attempt,
 recur exits with the code 255.
 
+recur sets the environment variable `RECUR_ATTEMPT` for the command it runs to the current attempt number.
+This way the command can access the attempt counter.
+recur also sets `RECUR_MAX_ATTEMPTS` to the value of `-a`/`--attempts`.
+
 ## Conditions
 
 recur supports a limited form of scripting.

main.go

@@ -43,6 +43,8 @@ import (
 )
 
 const (
+	envVarAttempt           = "RECUR_ATTEMPT"
+	envVarMaxAttempts       = "RECUR_MAX_ATTEMPTS"
 	exitCodeCommandNotFound = 255
 	exitCodeError           = -1
 	maxVerboseLevel         = 3
@@ -213,7 +215,7 @@ func evaluateCondition(attemptInfo attempt, expr string) (bool, error) {
 	return bool(val.Truth()), nil
 }
 
-func executeCommand(command string, args []string, timeout time.Duration) commandResult {
+func executeCommand(command string, args []string, timeout time.Duration, envVars []string) commandResult {
 	if _, err := exec.LookPath(command); err != nil {
 		return commandResult{
 			Status:   statusNotFound,
@@ -233,6 +235,10 @@ func executeCommand(command string, args []string, timeout time.Duration) comman
 	cmd.Stderr = os.Stderr
 	cmd.Stdin = os.Stdin
 
+	if len(envVars) > 0 {
+		cmd.Env = append(os.Environ(), envVars...)
+	}
+
 	err := cmd.Run()
 	if err != nil {
 		if ctx.Err() == context.DeadlineExceeded {
@@ -312,7 +318,11 @@ func retry(config retryConfig) (int, error) {
 			startTime = attemptStart
 		}
 
-		cmdResult = executeCommand(config.Command, config.Args, config.Timeout)
+		envVars := []string{
+			fmt.Sprintf("%s=%d", envVarAttempt, attemptNum),
+			fmt.Sprintf("%s=%d", envVarMaxAttempts, config.MaxAttempts),
+		}
+		cmdResult = executeCommand(config.Command, config.Args, config.Timeout, envVars)
 
 		attemptEnd := time.Now()
 		attemptDuration := attemptEnd.Sub(attemptStart)

main_test.go

@@ -29,6 +29,7 @@ import (
 )
 
 var (
+	commandEnv    = "test/env"
 	commandExit99 = "test/exit99"
 	commandHello  = "test/hello"
 	commandRecur  = "./recur"
@@ -70,19 +71,27 @@ func TestEcho(t *testing.T) {
 	}
 }
 
+func TestEnv(t *testing.T) {
+	_, _, err := runCommand(commandEnv)
+
+	if _, ok := err.(*exec.ExitError); ok {
+		t.Errorf("Expected exit status 0, got %v", err)
+	}
+}
+
 func TestExitCode(t *testing.T) {
 	_, _, err := runCommand(commandExit99)
 
 	if exitErr, ok := err.(*exec.ExitError); !ok || exitErr.ExitCode() != 99 {
-		t.Errorf("Expected exit code 99, got %v", err)
+		t.Errorf("Expected exit status 99, got %v", err)
 	}
 }
 
 func TestCommandNotFound(t *testing.T) {
 	_, _, err := runCommand(noSuchCommand)
 
 	if exitErr, ok := err.(*exec.ExitError); !ok || exitErr.ExitCode() != 255 {
-		t.Errorf("Expected exit code 255, got %v", err)
+		t.Errorf("Expected exit status 255, got %v", err)
 	}
 }
 
@@ -98,7 +107,7 @@ func TestAttemptsTrailingGarbageOptions(t *testing.T) {
 	_, _, err := runCommand("-a", "0abcdef", commandHello)
 
 	if exitErr, ok := err.(*exec.ExitError); !ok || exitErr.ExitCode() != 2 {
-		t.Errorf("Expected exit code 2, got %v", err)
+		t.Errorf("Expected exit status 2, got %v", err)
 	}
 }
 
@@ -182,7 +191,7 @@ func TestConditionExitArgNone(t *testing.T) {
 	_, _, err := runCommand("-c", "exit(None)", commandHello)
 
 	if exitErr, ok := err.(*exec.ExitError); !ok || exitErr.ExitCode() != 255 {
-		t.Errorf("Expected exit code 255, got %v", err)
+		t.Errorf("Expected exit status 255, got %v", err)
 	}
 }
 
@@ -194,7 +203,7 @@ func TestConditionExitArgTooLarge(t *testing.T) {
 	}
 
 	if exitErr, ok := err.(*exec.ExitError); !ok || exitErr.ExitCode() != 1 {
-		t.Errorf("Expected exit code 1, got %v", err)
+		t.Errorf("Expected exit status 1, got %v", err)
 	}
 }
 
@@ -206,7 +215,7 @@ func TestConditionExitArgWrongType(t *testing.T) {
 	}
 
 	if exitErr, ok := err.(*exec.ExitError); !ok || exitErr.ExitCode() != 1 {
-		t.Errorf("Expected exit code 1, got %v", err)
+		t.Errorf("Expected exit status 1, got %v", err)
 	}
 }
 
@@ -222,15 +231,15 @@ func TestConditionCommandNotFound(t *testing.T) {
 	_, _, err := runCommand("--condition", "command_found or exit(42)", noSuchCommand)
 
 	if exitErr, ok := err.(*exec.ExitError); !ok || exitErr.ExitCode() != 42 {
-		t.Errorf("Expected exit code 42, got %v", err)
+		t.Errorf("Expected exit status 42, got %v", err)
 	}
 }
 
 func TestConditionCommandNotFoundCode(t *testing.T) {
 	_, _, err := runCommand("--condition", "code == None and exit(42)", noSuchCommand)
 
 	if exitErr, ok := err.(*exec.ExitError); !ok || exitErr.ExitCode() != 42 {
-		t.Errorf("Expected exit code 42, got %v", err)
+		t.Errorf("Expected exit status 42, got %v", err)
 	}
 }
 

test.ps1

@@ -11,6 +11,7 @@ if (((Get-Variable 'IsWindows' -Scope 'Global' -ErrorAction 'Ignore') -and
 }
 $build = @{
     "recur" = "main.go"
+    "test/env" = "test/env.go"
     "test/exit99" = "test/exit99.go"
     "test/hello" = "test/hello.go"
     "test/sleep" = "test/sleep.go"

test/env.go

@@ -0,0 +1,29 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+)
+
+func main() {
+	envRecurAttempt := os.Getenv("RECUR_ATTEMPT")
+	attempt, err := strconv.Atoi(envRecurAttempt)
+	if err != nil {
+		fmt.Printf("%v\n", err)
+		os.Exit(101)
+	}
+
+	envRecurMaxAttempts := os.Getenv("RECUR_MAX_ATTEMPTS")
+	maxAttempts, err := strconv.Atoi(envRecurMaxAttempts)
+	if err != nil {
+		fmt.Printf("%v\n", err)
+		os.Exit(102)
+	}
+
+	if attempt == 3 && maxAttempts == 10 {
+		os.Exit(0)
+	} else {
+		os.Exit(103)
+	}
+}