From 0bd13c71739c4fb34feab4f7a169ee89bc77eee8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Iv=C3=A1n=20Ovejero?= <ivov.src@gmail.com>
Date: Wed, 7 Dec 2022 12:07:32 +0100
Subject: [PATCH] fix(core): Make expression resolution improvements (#4829)

:zap: Make expression resolution improvements
---
 packages/workflow/src/Expression.ts        |  9 ++---
 packages/workflow/src/WorkflowDataProxy.ts | 40 ++++++++++++++++++++--
 packages/workflow/test/Workflow.test.ts    | 18 ++++++++++
 3 files changed, 59 insertions(+), 8 deletions(-)

diff --git a/packages/workflow/src/Expression.ts b/packages/workflow/src/Expression.ts
index d0bacdc7cbd9f..ee049e98af9f3 100644
--- a/packages/workflow/src/Expression.ts
+++ b/packages/workflow/src/Expression.ts
@@ -254,6 +254,7 @@ export class Expression {
 		// Execute the expression
 		const returnValue = this.renderExpression(parameterValue, data);
 		if (typeof returnValue === 'function') {
+			if (returnValue.name === '$') throw new Error('invalid syntax');
 			throw new Error('Expression resolved to a function. Please add "()"');
 		} else if (typeof returnValue === 'string') {
 			return returnValue;
@@ -278,12 +279,8 @@ export class Expression {
 				}
 			}
 
-			if (
-				error instanceof Error &&
-				typeof error.message === 'string' &&
-				error.name === 'SyntaxError'
-			) {
-				throw new Error(error.message);
+			if (error instanceof Error && error.name === 'SyntaxError') {
+				throw new Error('invalid syntax');
 			}
 		}
 
diff --git a/packages/workflow/src/WorkflowDataProxy.ts b/packages/workflow/src/WorkflowDataProxy.ts
index 547b5622f85f3..45cb7775d60de 100644
--- a/packages/workflow/src/WorkflowDataProxy.ts
+++ b/packages/workflow/src/WorkflowDataProxy.ts
@@ -126,6 +126,10 @@ export class WorkflowDataProxy {
 		const that = this;
 		const node = this.workflow.nodes[nodeName];
 
+		if (!that.runExecutionData?.executionData && that.connectionInputData.length > 1) {
+			return {}; // incoming connection has pinned data, so stub context object
+		}
+
 		if (!that.runExecutionData?.executionData) {
 			throw new ExpressionError(
 				`The workflow hasn't been executed yet, so you can't reference any context data`,
@@ -332,7 +336,7 @@ export class WorkflowDataProxy {
 				);
 
 				if (nodeConnection === undefined) {
-					throw new ExpressionError(`connect ${that.activeNodeName} to ${nodeName}`, {
+					throw new ExpressionError(`connect "${that.activeNodeName}" to "${nodeName}"`, {
 						runIndex: that.runIndex,
 						itemIndex: that.itemIndex,
 					});
@@ -569,7 +573,39 @@ export class WorkflowDataProxy {
 			{},
 			{
 				get(target, name, receiver) {
-					return that.nodeDataGetter(name.toString());
+					const nodeName = name.toString();
+
+					if (that.workflow.getNode(nodeName) === null) {
+						throw new ExpressionError(`"${nodeName}" node doesn't exist`, {
+							runIndex: that.runIndex,
+							itemIndex: that.itemIndex,
+							failExecution: true,
+						});
+					}
+
+					if (
+						nodeName !== that.activeNodeName &&
+						!that.runExecutionData?.resultData.runData?.hasOwnProperty(nodeName)
+					) {
+						throw new ExpressionError(`no data, execute "${nodeName}" node first`, {
+							runIndex: that.runIndex,
+							itemIndex: that.itemIndex,
+							failExecution: true,
+						});
+					}
+
+					if (
+						nodeName !== that.activeNodeName &&
+						!that.workflow.getNodeConnectionIndexes(that.activeNodeName, nodeName, 'main')
+					) {
+						throw new ExpressionError(`connect "${that.activeNodeName}" to "${nodeName}"`, {
+							runIndex: that.runIndex,
+							itemIndex: that.itemIndex,
+							failExecution: true,
+						});
+					}
+
+					return that.nodeDataGetter(nodeName);
 				},
 			},
 		);
diff --git a/packages/workflow/test/Workflow.test.ts b/packages/workflow/test/Workflow.test.ts
index 2f8fa012542a9..98c151988be38 100644
--- a/packages/workflow/test/Workflow.test.ts
+++ b/packages/workflow/test/Workflow.test.ts
@@ -1057,6 +1057,11 @@ describe('Workflow', () => {
 				description:
 					'return resolved value when referencing another property with expression when a node has spaces (long "$node["{NODE}"].parameter" syntax)',
 				input: {
+					'Node 4 with spaces': {
+						parameters: {
+							value1: '',
+						},
+					},
 					Node1: {
 						parameters: {
 							value1: 'valueNode1',
@@ -1190,6 +1195,17 @@ describe('Workflow', () => {
 							],
 						],
 					},
+					'Node 4 with spaces': {
+						main: [
+							[
+								{
+									node: 'Node2',
+									type: 'main',
+									index: 0,
+								},
+							],
+						],
+					},
 				};
 
 				const workflow = new Workflow({ nodes, connections, active: false, nodeTypes });
@@ -1219,6 +1235,8 @@ describe('Workflow', () => {
 									},
 								},
 							],
+							Node2: [],
+							'Node 4 with spaces': [],
 						},
 					},
 				};