flutter_syntax_highlight 0.3.0

Dart-only syntax highlighting in two layers: a pure-Dart tokenizer underneath and a thin widget on top. The tokens rejoin into the exact input, byte for byte.

Changelog

0.3.0

SyntaxText now glides on a mouse wheel instead of jumping a notch at a time.

Breaking: the SDK floor is now Flutter 3.32 / Dart 3.8 (was 3.27 / 3.6). The wheel motion comes from flutter_smooth_wheel_scroll, which needs that floor. On Flutter 3.27–3.31, stay on 0.2.0.

• A wheel notch animates to its target with a spring, and notches during the motion add to the target. It never passes the start or end of the code. Shift+wheel moves sideways the same way, and a wheel turned over the scrollbar glides too, because the scrollbar shares the view's controller.
• Dragging, dragging the scrollbar, the keyboard and the trackpad move exactly as before.
• wheelMotion picks the motion: WheelMotion.spring (the default), .curve or .lerp, or null to move at once. It applies to both axes, and changing it keeps the scroll position.
• WheelMotion is exported from this package, so you do not need to depend on flutter_smooth_wheel_scroll yourself to pass one.
• How far a notch travels is app-wide and not set here — use SmoothWheelBinding from flutter_smooth_wheel_scroll in your main().
• The example gained a wheel demo: a code block longer and wider than the window, with a picker for the motion.

0.2.0

The palette derived from your ColorScheme now borrows your app's accent, in two places, diluted. Nothing else changed; the tokenizer is untouched.

• string (and escape, which follows its literal) is pulled from onSurfaceVariant towards tertiary; function, which had no style at all, is pulled from onSurface towards primary. number and punctuation stay where they were, so the literals gain a distinction between them.
• It still introduces no hue of its own — every colour is a neutral role from your scheme or a neutral role mixed with one of your scheme's accents, and a monochrome scheme still yields a monochrome palette.
• How far to pull was measured over the whole hue circle in both brightnesses, against two scales this palette already contained. See docs/adr/0003-the-derived-default-borrows-the-app-s-accent-diluted.md.
• The example gained a seed picker, so the derivation is visible rather than merely claimed.

Named presets are unchanged. If you pass one, or your own SyntaxPalette, nothing about this release affects you.

0.1.0

First release.

Tokenizer

• tokenizeDart(String source) returns a List<DartToken> whose texts concatenate back to the input, byte for byte. Tokens are cut at recorded offsets and never rebuilt, so CRLF and letter case survive unchanged.
• The file imports nothing — not Flutter, not dart:* — and a test fails if that ever stops being true.
• Eight kinds, every one decidable by scanning characters left to right: plain, comment, keyword, string, number, punctuation, escape, function. Distinctions that need a parser are deliberately absent; the reasoning is in docs/adr/0001-token-kinds-are-lexical-only.md.
• The inside of ${...} is scanned recursively with the same rules as the outside, so a string nested in an interpolation comes back out as a string. Nested block comments, raw strings, triple-quoted strings, and unterminated strings and interpolations are each handled, the last two by stopping at the end of the line.

Widget

• SyntaxText(source, {palette, copyable, scrollable, fontFamily, fontFamilyFallback, fontSize, height, padding, copyTooltip, copiedTooltip}) draws selectable, copyable code. It takes a string, not an asset key, so it has no loading state.
• Horizontal scrolling is always owned by the widget — code does not wrap. scrollable governs the vertical axis only.
• SyntaxPalette holds one optional TextStyle per kind plus an optional background. SyntaxPalette.fromColorScheme derives the default from the consumer's ColorScheme without introducing a hue of its own, and paints no background, so it is right in light and dark with nothing to configure.
• Ten named presets — solarizedDark, solarizedLight, oneDark, oneLight, monokai, gruvboxDark, gruvboxLight, tokyoNight, tokyoNightLight, cobalt2 — each an excerpt of an MIT-licensed upstream theme, carrying the background its colours were chosen against. Provenance, pinned commit by pinned commit, is in NOTICES.