From 7a9fbda3500c3c6328240dce2cf5c59e0fddc6df Mon Sep 17 00:00:00 2001
From: hovsep <avakyan.hovsep@yandex.ru>
Date: Tue, 17 Sep 2024 02:09:36 +0300
Subject: [PATCH] Component: better waiting for inputs api

---
 component/component.go      |  4 ++--
 component/component_test.go | 27 ++++++++++++++++++++++---
 component/errors.go         | 18 +++++++++++------
 component/errors_test.go    | 39 -------------------------------------
 fmesh_test.go               |  2 +-
 5 files changed, 39 insertions(+), 51 deletions(-)
 delete mode 100644 component/errors_test.go

diff --git a/component/component.go b/component/component.go
index 9523474..16916c9 100644
--- a/component/component.go
+++ b/component/component.go
@@ -102,10 +102,10 @@ func (c *Component) MaybeActivate() (activationResult *ActivationResult) {
 	//Run the computation
 	err := c.f(c.inputs, c.outputs)
 
-	if IsWaitingForInputError(err) {
+	if errors.Is(err, errWaitingForInputs) {
 		activationResult = c.newActivationCodeWaitingForInput()
 
-		if !errors.Is(err, ErrWaitingForInputKeepInputs) {
+		if !errors.Is(err, errWaitingForInputsKeep) {
 			c.inputs.ClearSignal()
 		}
 
diff --git a/component/component_test.go b/component/component_test.go
index 2875d4d..54d0507 100644
--- a/component/component_test.go
+++ b/component/component_test.go
@@ -420,7 +420,7 @@ func TestComponent_MaybeActivate(t *testing.T) {
 					WithActivationFunc(func(inputs port.Collection, outputs port.Collection) error {
 
 						if !inputs.ByNames("i1", "i2").AllHaveSignal() {
-							return ErrWaitingForInputResetInputs
+							return NewErrWaitForInputs(false)
 						}
 
 						return nil
@@ -432,14 +432,35 @@ func TestComponent_MaybeActivate(t *testing.T) {
 				WithActivationCode(ActivationCodeNoInput),
 		},
 		{
-			name: "component is waiting for input",
+			name: "component is waiting for input, reset inputs",
 			getComponent: func() *Component {
 				c := NewComponent("c1").
 					WithInputs("i1", "i2").
 					WithActivationFunc(func(inputs port.Collection, outputs port.Collection) error {
 
 						if !inputs.ByNames("i1", "i2").AllHaveSignal() {
-							return ErrWaitingForInputResetInputs
+							return NewErrWaitForInputs(false)
+						}
+
+						return nil
+					})
+				//Only one input set
+				c.Inputs().ByName("i1").PutSignal(signal.New(123))
+				return c
+			},
+			wantActivationResult: NewActivationResult("c1").
+				SetActivated(false).
+				WithActivationCode(ActivationCodeWaitingForInput),
+		},
+		{
+			name: "component is waiting for input, keep inputs",
+			getComponent: func() *Component {
+				c := NewComponent("c1").
+					WithInputs("i1", "i2").
+					WithActivationFunc(func(inputs port.Collection, outputs port.Collection) error {
+
+						if !inputs.ByNames("i1", "i2").AllHaveSignal() {
+							return NewErrWaitForInputs(true)
 						}
 
 						return nil
diff --git a/component/errors.go b/component/errors.go
index 4708a4e..671df5f 100644
--- a/component/errors.go
+++ b/component/errors.go
@@ -1,13 +1,19 @@
 package component
 
-import "errors"
+import (
+	"errors"
+	"fmt"
+)
 
 var (
-	//@TODO: provide wrapper methods so exact input can be specified within error
-	ErrWaitingForInputResetInputs = errors.New("component is waiting for one or more inputs. All inputs will be reset")
-	ErrWaitingForInputKeepInputs  = errors.New("component is waiting for one or more inputs. All inputs will be kept")
+	errWaitingForInputs     = errors.New("component is waiting for some inputs")
+	errWaitingForInputsKeep = fmt.Errorf("%w: do not clear input ports", errWaitingForInputs)
 )
 
-func IsWaitingForInputError(err error) bool {
-	return errors.Is(err, ErrWaitingForInputResetInputs) || errors.Is(err, ErrWaitingForInputKeepInputs)
+// NewErrWaitForInputs returns respective error
+func NewErrWaitForInputs(keepInputs bool) error {
+	if keepInputs {
+		return errWaitingForInputsKeep
+	}
+	return errWaitingForInputs
 }
diff --git a/component/errors_test.go b/component/errors_test.go
deleted file mode 100644
index b1a631b..0000000
--- a/component/errors_test.go
+++ /dev/null
@@ -1,39 +0,0 @@
-package component
-
-import (
-	"errors"
-	"testing"
-)
-
-func TestIsWaitingForInputError(t *testing.T) {
-	type args struct {
-		err error
-	}
-	tests := []struct {
-		name string
-		args args
-		want bool
-	}{
-		{
-			name: "no",
-			args: args{
-				err: errors.New("test error"),
-			},
-			want: false,
-		},
-		{
-			name: "yes",
-			args: args{
-				err: ErrWaitingForInputKeepInputs,
-			},
-			want: true,
-		},
-	}
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			if got := IsWaitingForInputError(tt.args.err); got != tt.want {
-				t.Errorf("IsWaitingForInputError() = %v, want %v", got, tt.want)
-			}
-		})
-	}
-}
diff --git a/fmesh_test.go b/fmesh_test.go
index 5cfb484..3cb8b93 100644
--- a/fmesh_test.go
+++ b/fmesh_test.go
@@ -669,7 +669,7 @@ func TestFMesh_runCycle(t *testing.T) {
 					WithOutputs("o1").
 					WithActivationFunc(func(inputs port.Collection, outputs port.Collection) error {
 						if !inputs.ByNames("i1", "i2").AllHaveSignal() {
-							return component.ErrWaitingForInputKeepInputs
+							return component.NewErrWaitForInputs(true)
 						}
 						return nil
 					}),