feat: add AfterRun() hook

Fixes #288

context.go

@@ -809,18 +809,22 @@ func (c *Context) RunNode(node *Node, binds ...interface{}) (err error) {
 func (c *Context) Run(binds ...interface{}) (err error) {
 	node := c.Selected()
 	if node == nil {
-		if len(c.Path) > 0 {
-			selected := c.Path[0].Node()
-			if selected.Type == ApplicationNode {
-				method := getMethod(selected.Target, "Run")
-				if method.IsValid() {
-					return c.RunNode(selected, binds...)
-				}
+		if len(c.Path) == 0 {
+			return fmt.Errorf("no command selected")
+		}
+		selected := c.Path[0].Node()
+		if selected.Type == ApplicationNode {
+			method := getMethod(selected.Target, "Run")
+			if method.IsValid() {
+				node = selected
 			}
+		} else {
+			return fmt.Errorf("no command selected")
 		}
-		return fmt.Errorf("no command selected")
 	}
-	return c.RunNode(node, binds...)
+	runErr := c.RunNode(node, binds...)
+	err = c.Kong.applyHook(c, "AfterRun")
+	return errors.Join(runErr, err)
 }
 
 // PrintUsage to Kong's stdout.

go.mod

@@ -7,4 +7,4 @@ require (
 
 require github.com/hexops/gotextdiff v1.0.3 // indirect
 
-go 1.18
+go 1.20

go.sum

@@ -1,5 +1,3 @@
-github.com/alecthomas/assert/v2 v2.10.0 h1:jjRCHsj6hBJhkmhznrCzoNpbA3zqy0fYiUcYZP/GkPY=
-github.com/alecthomas/assert/v2 v2.10.0/go.mod h1:Bze95FyfUr7x34QZrjL+XP+0qgp/zg8yS+TtBj1WA3k=
 github.com/alecthomas/assert/v2 v2.11.0 h1:2Q9r3ki8+JYXvGsDyBXwH3LcJ+WK5D0gc5E8vS6K3D0=
 github.com/alecthomas/assert/v2 v2.11.0/go.mod h1:Bze95FyfUr7x34QZrjL+XP+0qgp/zg8yS+TtBj1WA3k=
 github.com/alecthomas/repr v0.4.0 h1:GhI2A8MACjfegCPVq9f1FLvIBS+DrQ2KQBFZP1iFzXc=

hooks.go

@@ -3,17 +3,24 @@ package kong
 // BeforeResolve is a documentation-only interface describing hooks that run before resolvers are applied.
 type BeforeResolve interface {
 	// This is not the correct signature - see README for details.
-	BeforeResolve(args ...interface{}) error
+	BeforeResolve(args ...any) error
 }
 
 // BeforeApply is a documentation-only interface describing hooks that run before values are set.
 type BeforeApply interface {
 	// This is not the correct signature - see README for details.
-	BeforeApply(args ...interface{}) error
+	BeforeApply(args ...any) error
 }
 
 // AfterApply is a documentation-only interface describing hooks that run after values are set.
 type AfterApply interface {
 	// This is not the correct signature - see README for details.
-	AfterApply(args ...interface{}) error
+	AfterApply(args ...any) error
+}
+
+// AfterRun is a documentation-only interface describing hooks that run after Run() returns.
+type AfterRun interface {
+	// This is not the correct signature - see README for details.
+	// AfterRun is called after Run() returns.
+	AfterRun(args ...any) error
 }

kong_test.go

@@ -2327,3 +2327,28 @@ func TestRecursiveVariableExpansion(t *testing.T) {
 	assert.NoError(t, err)
 	assert.Contains(t, w.String(), "Default: /etc/config")
 }
+
+type afterRunCLI struct {
+	runCalled      bool `kong:"-"`
+	afterRunCalled bool `kong:"-"`
+}
+
+func (c *afterRunCLI) Run() error {
+	c.runCalled = true
+	return nil
+}
+
+func (c *afterRunCLI) AfterRun() error {
+	c.afterRunCalled = true
+	return nil
+}
+
+func TestAfterRun(t *testing.T) {
+	var cli afterRunCLI
+	k := mustNew(t, &cli)
+	kctx, err := k.Parse([]string{})
+	assert.NoError(t, err)
+	err = kctx.Run()
+	assert.NoError(t, err)
+	assert.Equal(t, afterRunCLI{runCalled: true, afterRunCalled: true}, cli)
+}