Merge pull request #15 from dispatchrun/simplify-unit-testing

Simplify unit testing using new `dispatchtest.Call` helper

dispatchtest/integration/main.go

@@ -40,12 +40,9 @@ func run() error {
 		return strings.Repeat(stringified, doubled), nil
 	})
 
-	call, err := doubleAndRepeat.BuildCall(4)
-	if err != nil {
-		return fmt.Errorf("new call failed: %v", err)
-	}
+	runner := dispatchtest.NewRunner(stringify, double, doubleAndRepeat)
 
-	output, err := dispatchtest.Run[string](call, stringify, double, doubleAndRepeat)
+	output, err := dispatchtest.Call(runner, doubleAndRepeat, 4)
 	if err != nil {
 		return err
 	}

dispatchtest/run.go

@@ -11,26 +11,33 @@ import (
 	"github.com/dispatchrun/dispatch-go/dispatchproto"
 )
 
-// Run runs a function and returns its result.
-func Run[O any](call dispatchproto.Call, functions ...dispatch.AnyFunction) (O, error) {
-	runner := NewRunner(functions...)
+// Call calls a dispatch.Function using the specified Runner.
+func Call[I, O any](runner *Runner, fn *dispatch.Function[I, O], input I) (O, error) {
+	// Note: runner.Call[I, O] isn't possible because Go doesn't support generic methods.
+
+	var zero O
+	call, err := fn.BuildCall(input)
+	if err != nil {
+		return zero, err
+	}
 
 	res := runner.Run(call.Request())
 
-	var output O
 	result, ok := res.Result()
 	if !ok {
 		if !res.OK() {
-			return output, dispatchproto.StatusError(res.Status())
+			return zero, dispatchproto.StatusError(res.Status())
 		}
-		return output, fmt.Errorf("unexpected response: %s", res)
+		return zero, fmt.Errorf("unexpected response: %s", res)
 	}
-	var err error
+
 	if resultErr, ok := result.Error(); ok {
 		err = resultErr
 	} else if !res.OK() {
 		err = dispatchproto.StatusError(res.Status())
 	}
+
+	var output O
 	boxedOutput, ok := res.Output()
 	if ok {
 		if unmarshalErr := boxedOutput.Unmarshal(&output); err == nil && unmarshalErr != nil {

function_test.go

@@ -36,23 +36,16 @@ func TestCoroutineReturn(t *testing.T) {
 		return strconv.Itoa(in), nil
 	})
 
-	call, err := stringify.BuildCall(11)
-	if err != nil {
-		t.Fatal(err)
-	}
-	output, err := dispatchtest.Run[string](call, stringify)
+	runner := dispatchtest.NewRunner(stringify)
+
+	output, err := dispatchtest.Call(runner, stringify, 11)
 	if err != nil {
 		t.Fatal(err)
-	}
-	if output != "11" {
+	} else if output != "11" {
 		t.Errorf("unexpected output: %s", output)
 	}
 
-	call2, err := stringify.BuildCall(-23)
-	if err != nil {
-		t.Fatal(err)
-	}
-	_, err = dispatchtest.Run[string](call2, stringify)
+	_, err = dispatchtest.Call(runner, stringify, -23)
 	if err == nil || !strings.Contains(err.Error(), "InvalidArgument: -23") {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -72,23 +65,16 @@ func TestCoroutineExit(t *testing.T) {
 		panic("unreachable")
 	})
 
-	call, err := stringify.BuildCall(11)
-	if err != nil {
-		t.Fatal(err)
-	}
-	output, err := dispatchtest.Run[string](call, stringify)
+	runner := dispatchtest.NewRunner(stringify)
+
+	output, err := dispatchtest.Call(runner, stringify, 11)
 	if err != nil {
 		t.Fatal(err)
-	}
-	if output != "11" {
+	} else if output != "11" {
 		t.Errorf("unexpected output: %s", output)
 	}
 
-	call2, err := stringify.BuildCall(-23)
-	if err != nil {
-		t.Fatal(err)
-	}
-	_, err = dispatchtest.Run[string](call2, stringify)
+	_, err = dispatchtest.Call(runner, stringify, -23)
 	if err == nil || !strings.Contains(err.Error(), "InvalidArgument: -23") {
 		t.Fatalf("unexpected error: %v", err)
 	}