flutter_diff_viewer 1.4.0

A production-grade Flutter package providing GitHub/GitLab-style content comparison and diff viewing. Supports side-by-side, unified, and stacked layouts with line, word, and character-level diff granularity.

Changelog

All notable changes to this project will be documented in this file.

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

1.4.0 - 2026-08-31

Added

• Visual Added Whitespace Highlighting (highlightWhitespace): Added highlightWhitespace flag in FlutterDiffViewerConfiguration (defaults to true) to visually highlight added/extra whitespace characters (· for spaces, → for tabs).
• Customizable Whitespace Color Tokens: Added addedWhitespaceBackgroundColor and addedWhitespaceTextColor in FlutterDiffViewerTheme with vibrant default badge styling to make added/extra whitespace stand out clearly.
• Synchronized Full-View Horizontal Scrolling (DiffHorizontalScrollSync): Unified horizontal scrolling across all line rows in a panel so lines scroll together smoothly without single-line drift or layout performance bottlenecks.

1.3.3 - 2026-08-24

Fixed

• Identical Content Line Population: Fixed DiffRepositoryImpl to populate unchanged text lines for identical inputs, enabling the left panel ("Current") to display current version text when isCentralizedNoChanges: false.
• Studio Switch Editors: Added boolean switch editors for isCentralizedNoChanges, showContentWhenIdentical, and showHeaderDivider in the interactive Customization Studio.

1.3.2 - 2026-08-24

Added

• Redesigned Header Bar (Title + Version Badge): Headers now render a clean "Title" + "Version Badge" layout (e.g., "Current V1.1"). Added oldVersionCode and newVersionCode parameters.
• Custom Version Widget Overrides: Added oldVersionWidget and newVersionWidget to replace default version badges with custom widgets.
• Optional Header Bottom Divider (showHeaderDivider): Header bottom divider is now off by default (false) for a clean borderless look, and fully configurable in FlutterDiffViewerTheme.
• Configurable Version Badge Styling: Customizable badge colors (versionBadgeBackgroundColor, versionBadgeTextColor, versionBadgeBorderRadius), typography (versionBadgeStyle), and padding (versionBadgeHorizontalPadding, versionBadgeVerticalPadding).
• Configurable Centralized Empty State (isCentralizedNoChanges): Added isCentralizedNoChanges flag in FlutterDiffViewerConfiguration (default: true). When set to false, displays current content on the left panel and a panel-level empty state on the right panel.
• Configurable Empty State (showContentWhenIdentical): Added showContentWhenIdentical flag in FlutterDiffViewerConfiguration. When set to true, renders identical content as unchanged lines instead of hiding content behind the empty state.
• Interactive Studio Updates: Added interactive controls and code generator support for isCentralizedNoChanges, showContentWhenIdentical, and showHeaderDivider in the demo studio.

1.1.0 - 2026-08-20

Added

• Split Dual-Card Panel Mode (splitPanels): Render original and modified diff views as two distinct separate card containers.
• Customizable In-Between Box Gap (panelSpacing): Responsive spacing gap in pixels between the left/original and right/modified panel cards.
• Customizable Card Box Borders & Radius: Added panelBorderRadius and panelBorderWidth in DiffSpacing, plus panelBackgroundColor and panelBorderColor in FlutterDiffViewerTheme.
• Card-Embedded Version Headers: In split panel mode, version titles ("Current V1.1", "Modified V1.2") render cleanly inside each card header bar.

1.0.0 - 2026-08-17

Added

• Initial release of flutter_diff_viewer
• GitHub/GitLab-style side-by-side diff view
• Unified diff view (single-column with +/- indicators)
• Stacked diff view (optimized for narrow/mobile screens)
• Line-level diff calculation using Myers LCS algorithm
• Word-level inline diff highlighting
• Character-level inline diff highlighting
• Staged diff processing (line → word → character, changed lines only)
• FlutterDiffViewer main widget with simple and advanced API
• FlutterDiffViewerController for programmatic navigation
• FlutterDiffViewerConfiguration — fully immutable configuration object
• FlutterDiffViewerTheme with light() and dark() factory constructors
• DiffTypography — full text style customization
• DiffSpacing — layout spacing customization
• DiffLocalizations — localization/i18n support
• Custom builder callbacks: headerBuilder, lineBuilder, lineNumberBuilder, indicatorBuilder, segmentBuilder, summaryBuilder, emptyStateBuilder, errorBuilder, loadingBuilder, collapsedSectionBuilder, footerBuilder
• DiffEngine abstract interface for pluggable diff algorithms
• Replaceable diff engine via FlutterDiffViewer(diffEngine: myEngine)
• Synchronized scrolling for side-by-side view
• Collapsible unchanged sections with configurable contextLines
• Change navigation: next/previous/go-to change
• Line numbers, indicators (+/-/space), headers, summary widget
• Responsive layout via LayoutBuilder
• Accessibility: semantic labels, screen reader support, color-independent indicators
• Async diff processing with compute() for large documents (>1000 lines)
• ListView.builder rendering — handles 50,000+ line documents efficiently
• Proper lifecycle management — no controller or scroll leaks
• Full null safety (Dart 3.x)
• Comprehensive unit, widget, and integration tests
• Full API documentation
• Professional example application with 10+ screens