From 95ed3c5c929e7f9632edb92f67370901f162a3d9 Mon Sep 17 00:00:00 2001
From: Csaba Tuncsik <csaba@n8n.io>
Date: Wed, 6 Aug 2025 18:53:35 +0200
Subject: [PATCH] fix(editor): Improve workflow diff components (#18018)

---
 .../design-system/src/css/_tokens.dark.scss   |  11 ++
 .../@n8n/design-system/src/css/_tokens.scss   |  11 ++
 .../src/features/workflow-diff/NodeDiff.vue   | 114 +++++++++++++++++-
 .../workflow-diff/WorkflowDiffAside.vue       |  22 ++--
 .../workflow-diff/WorkflowDiffModal.vue       |  48 +++-----
 5 files changed, 166 insertions(+), 40 deletions(-)

diff --git a/packages/frontend/@n8n/design-system/src/css/_tokens.dark.scss b/packages/frontend/@n8n/design-system/src/css/_tokens.dark.scss
index da09d1528a..6321beaa3c 100644
--- a/packages/frontend/@n8n/design-system/src/css/_tokens.dark.scss
+++ b/packages/frontend/@n8n/design-system/src/css/_tokens.dark.scss
@@ -4,6 +4,17 @@
 	// Primary tokens
 	--color-danger: var(--prim-color-alt-k);
 
+	// Diff colors (dark theme overrides)
+	--diff-new: #38cb7a;
+	--diff-new-light: #43674f;
+	--diff-new-faint: #3a463e;
+	--diff-modified: #d6a625;
+	--diff-modified-light: #6a5c38;
+	--diff-modified-faint: #464236;
+	--diff-del: #fb887a;
+	--diff-del-light: #7a524e;
+	--diff-del-faint: #4d3e3d;
+
 	// Text
 	--color-text-dark: var(--prim-gray-40);
 	--color-text-base: var(--prim-gray-200);
diff --git a/packages/frontend/@n8n/design-system/src/css/_tokens.scss b/packages/frontend/@n8n/design-system/src/css/_tokens.scss
index 9733095368..ca6f941527 100644
--- a/packages/frontend/@n8n/design-system/src/css/_tokens.scss
+++ b/packages/frontend/@n8n/design-system/src/css/_tokens.scss
@@ -42,6 +42,17 @@
 	--color-danger-tint-1: var(--prim-color-alt-c-tint-400);
 	--color-danger-tint-2: var(--prim-color-alt-c-tint-450);
 
+	// Diff colors
+	--diff-new: #0eab54;
+	--diff-new-light: #b4efc4;
+	--diff-new-faint: #ddfbe7;
+	--diff-modified: #bf941f;
+	--diff-modified-light: #f3dca1;
+	--diff-modified-faint: #fbf1d4;
+	--diff-del: #f51f32;
+	--diff-del-light: #fad3d0;
+	--diff-del-faint: #ffedec;
+
 	// Text
 	--color-text-dark: var(--prim-gray-740);
 	--color-text-base: var(--prim-gray-540);
diff --git a/packages/frontend/editor-ui/src/features/workflow-diff/NodeDiff.vue b/packages/frontend/editor-ui/src/features/workflow-diff/NodeDiff.vue
index 17dc0d272e..4b86c5ce26 100644
--- a/packages/frontend/editor-ui/src/features/workflow-diff/NodeDiff.vue
+++ b/packages/frontend/editor-ui/src/features/workflow-diff/NodeDiff.vue
@@ -24,11 +24,123 @@ const props = withDefaults(
 	<CodeDiff v-bind="props" class="code-diff" />
 </template>
 
-<style scoped>
+<style lang="scss">
+/* Diff colors are now centralized in @n8n/design-system tokens */
+
 .code-diff {
 	height: 100%;
 	margin: 0;
 	border: none;
 	border-radius: 0;
+
+	// Dark theme support for v-code-diff
+	[data-theme='dark'] & {
+		// Main container and wrapper (primary background)
+		background: var(--color-background-light) !important; // Dark background in dark theme
+		color: var(--color-text-dark) !important; // In dark theme: light text
+
+		// Target all possible wrapper elements
+		> div,
+		.v-code-diff,
+		.v-code-diff-wrapper,
+		.code-diff-wrapper,
+		.diff-wrapper {
+			background: var(--color-background-light) !important;
+		}
+
+		// Code diff view wrapper
+		.code-diff-view {
+			background: var(--color-background-light) !important; // Dark background
+			color: var(--color-text-dark) !important;
+		}
+
+		// Main table wrapper
+		.diff-table {
+			background: var(--color-background-light) !important; // Dark background
+			color: var(--color-text-dark) !important;
+		}
+
+		// Line numbers (slightly emphasized background)
+		.blob-num {
+			background: var(--color-background-darker) !important; // In dark theme: even lighter gray
+			color: var(--color-text-light) !important; // Muted text
+			border-color: var(--color-foreground-base) !important;
+		}
+
+		// Context lines (unchanged code - dark background for better contrast)
+		.blob-num-context {
+			background: var(--color-background-light) !important; // Dark background in dark theme
+			color: var(--color-text-light) !important; // Muted text
+		}
+
+		.blob-code-context {
+			background: var(--color-background-light) !important; // Dark background in dark theme
+			color: var(--color-text-dark) !important; // Primary text
+		}
+
+		// Added lines (insertions)
+		.blob-num-addition {
+			background: var(--diff-new-light) !important;
+			color: var(--color-text-xlight) !important;
+			border-color: var(--diff-new) !important;
+		}
+
+		.blob-code-addition {
+			background: var(--diff-new-faint) !important;
+			color: var(--color-text-xlight) !important;
+		}
+
+		// Deleted lines
+		.blob-num-deletion {
+			background: var(--diff-del-light) !important;
+			color: var(--color-text-xlight) !important;
+			border-color: var(--diff-del) !important;
+		}
+
+		.blob-code-deletion {
+			background: var(--diff-del-faint) !important;
+			color: var(--color-text-xlight) !important;
+		}
+
+		// Hunk headers
+		.blob-num-hunk,
+		.blob-code-hunk {
+			background: var(--color-background-medium) !important;
+			color: var(--color-text-base) !important;
+		}
+
+		// Code markers and inner content
+		.blob-code-inner {
+			color: var(--color-text-dark) !important;
+		}
+
+		// Syntax highlighting overrides for dark theme
+		.hljs-attr {
+			color: #79c0ff !important;
+		}
+
+		.hljs-string {
+			color: #a5d6ff !important;
+		}
+
+		.hljs-number {
+			color: #79c0ff !important;
+		}
+
+		.hljs-punctuation {
+			color: var(--color-text-light) !important;
+		}
+
+		.hljs-keyword,
+		.hljs-literal {
+			color: #ff7b72 !important;
+		}
+
+		// Character-level diff highlighting
+		.x {
+			background: rgba(255, 255, 255, 0.1) !important;
+			color: inherit !important;
+		}
+	}
 }
 </style>
diff --git a/packages/frontend/editor-ui/src/features/workflow-diff/WorkflowDiffAside.vue b/packages/frontend/editor-ui/src/features/workflow-diff/WorkflowDiffAside.vue
index 66e9ba1552..5771758277 100644
--- a/packages/frontend/editor-ui/src/features/workflow-diff/WorkflowDiffAside.vue
+++ b/packages/frontend/editor-ui/src/features/workflow-diff/WorkflowDiffAside.vue
@@ -21,9 +21,6 @@ function onResize({ width }: { width: number }) {
 }
 
 const outputFormat = ref<'side-by-side' | 'line-by-line'>('line-by-line');
-function toggleOutputFormat() {
-	outputFormat.value = outputFormat.value === 'line-by-line' ? 'side-by-side' : 'line-by-line';
-}
 
 const emit = defineEmits<{
 	close: [];
@@ -44,22 +41,22 @@ const emit = defineEmits<{
 			style="display: flex; flex-direction: row; align-items: center; gap: 8px; padding: 12px 10px"
 		>
 			<NodeIcon class="ml-xs" :node-type :size="16" />
-			<N8nHeading size="small" color="text-dark" bold>
+			<N8nHeading size="small" color="text-dark" bold :class="$style.nodeTitle">
 				{{ node.name }}
 			</N8nHeading>
 			<N8nIconButton
-				icon="file-diff"
+				icon="x"
 				type="secondary"
+				text
 				class="ml-auto"
-				@click="toggleOutputFormat"
+				@click="emit('close')"
 			></N8nIconButton>
-			<N8nIconButton icon="x" type="secondary" text @click="emit('close')"></N8nIconButton>
 		</div>
-		<slot v-bind="{ outputFormat, toggleOutputFormat }" />
+		<slot v-bind="{ outputFormat }" />
 	</N8nResizeWrapper>
 </template>
 
-<style module>
+<style module lang="scss">
 .workflowDiffAside {
 	width: calc(v-bind(panelWidth) * 1px);
 	display: flex;
@@ -68,4 +65,11 @@ const emit = defineEmits<{
 	border-left: 1px solid var(--color-foreground-base);
 	border-top: 1px solid var(--color-foreground-base);
 }
+
+.nodeTitle {
+	flex: 1;
+	overflow: hidden;
+	text-overflow: ellipsis;
+	white-space: nowrap;
+}
 </style>
diff --git a/packages/frontend/editor-ui/src/features/workflow-diff/WorkflowDiffModal.vue b/packages/frontend/editor-ui/src/features/workflow-diff/WorkflowDiffModal.vue
index 8c9fde739a..5d3b289883 100644
--- a/packages/frontend/editor-ui/src/features/workflow-diff/WorkflowDiffModal.vue
+++ b/packages/frontend/editor-ui/src/features/workflow-diff/WorkflowDiffModal.vue
@@ -399,7 +399,7 @@ const modifiers = [
 											>
 												<DiffBadge :type="change.status" />
 												<NodeIcon :node-type="change.type" :size="16" class="ml-2xs mr-4xs" />
-												{{ change.node.name }}
+												<span :class="$style.nodeName">{{ change.node.name }}</span>
 											</ElDropdownItem>
 										</ul>
 										<ul v-if="activeTab === 'connectors'" :class="$style.changes">
@@ -407,7 +407,7 @@ const modifiers = [
 												<div>
 													<DiffBadge :type="change[1].status" />
 												</div>
-												<div style="flex: 1">
+												<div style="flex: 1; min-width: 0">
 													<ul :class="$style.changesNested">
 														<ElDropdownItem
 															:class="{
@@ -424,7 +424,9 @@ const modifiers = [
 																:size="16"
 																class="ml-2xs mr-4xs"
 															/>
-															{{ change[1].connection.source?.name }}
+															<span :class="$style.nodeName">{{
+																change[1].connection.source?.name
+															}}</span>
 														</ElDropdownItem>
 														<div :class="$style.separator"></div>
 														<ElDropdownItem
@@ -442,7 +444,9 @@ const modifiers = [
 																:size="16"
 																class="ml-2xs mr-4xs"
 															/>
-															{{ change[1].connection.target?.name }}
+															<span :class="$style.nodeName">{{
+																change[1].connection.target?.name
+															}}</span>
 														</ElDropdownItem>
 													</ul>
 												</div>
@@ -588,32 +592,7 @@ const modifiers = [
 </template>
 
 <style module lang="scss">
-/* Light theme diff colors */
-:root,
-[data-theme='light'] {
-	--diff-new: #0eab54;
-	--diff-new-light: #b4efc4;
-	--diff-new-faint: #ddfbe7;
-	--diff-modified: #bf941f;
-	--diff-modified-light: #f3dca1;
-	--diff-modified-faint: #fbf1d4;
-	--diff-del: #f51f32;
-	--diff-del-light: #fad3d0;
-	--diff-del-faint: #ffedec;
-}
-
-/* Dark theme diff colors */
-[data-theme='dark'] {
-	--diff-new: #38cb7a;
-	--diff-new-light: #43674f;
-	--diff-new-faint: #3a463e;
-	--diff-modified: #d6a625;
-	--diff-modified-light: #6a5c38;
-	--diff-modified-faint: #464236;
-	--diff-del: #fb887a;
-	--diff-del-light: #7a524e;
-	--diff-del-faint: #4d3e3d;
-}
+/* Diff colors are now centralized in @n8n/design-system tokens */
 
 .workflowDiffModal {
 	margin-bottom: 0;
@@ -690,12 +669,21 @@ const modifiers = [
 	border-radius: 4px;
 	padding: var(--spacing-xs) var(--spacing-2xs);
 	line-height: unset;
+	min-width: 0;
 }
 
 .clickableChangeActive {
 	background-color: var(--color-background-medium);
 }
 
+.nodeName {
+	flex: 1;
+	overflow: hidden;
+	text-overflow: ellipsis;
+	white-space: nowrap;
+	min-width: 0;
+}
+
 .separator {
 	width: 1px;
 	height: 10px;