[shaping] cleanup and adjust tests

go-text · Nov 1, 2023 · d06f064 · d06f064
1 parent f491679
commit d06f064
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Showing 3 changed files with 69 additions and 58 deletions.
diff --git a/shaping/output.go b/shaping/output.go
@@ -129,8 +129,8 @@ func (o *Output) RecomputeAdvance() {
 }
 
 // advanceSpaceAware adjust the value in [Advance]
-// if a white space character end the run.
-// TODO: should be take into account multiple spaces ?
+// if a white space character ends the run.
+// TODO: should we take into account multiple spaces ?
 func (o *Output) advanceSpaceAware() fixed.Int26_6 {
 	L := len(o.Glyphs)
 	if L == 0 {

diff --git a/shaping/wrapping.go b/shaping/wrapping.go
@@ -816,6 +816,55 @@ type lineConfig struct {
 	truncatedMaxWidth int
 }
 
+func (l *LineWrapper) postProcessLine(finalLine Line, done bool) (Line, int, bool) {
+	if len(finalLine) > 0 {
+		finalRun := finalLine[len(finalLine)-1]
+
+		// zero trailing whitespace advance,
+		// to be coherent with Output.advanceSpaceAware
+		if L := len(finalRun.Glyphs); L != 0 {
+			if finalRun.Direction.IsVertical() {
+				if g := &finalRun.Glyphs[L-1]; g.Height == 0 {
+					g.YAdvance = 0
+				}
+			} else { // horizontal
+				if g := finalRun.Glyphs[L-1]; g.Width == 0 {
+					g.XAdvance = 0
+				}
+			}
+			finalRun.RecomputeAdvance()
+		}
+
+		// Update the start position of the next line.
+		l.lineStartRune = finalRun.Runes.Count + finalRun.Runes.Offset
+	}
+
+	// Check whether we've exhausted the text.
+	done = done || l.lineStartRune >= l.breaker.totalRunes
+
+	// Implement truncation if needed.
+	truncated := 0
+	if l.truncating {
+		l.config.TruncateAfterLines--
+		insertTruncator := false
+		if l.config.TruncateAfterLines == 0 {
+			done = true
+			truncated = l.breaker.totalRunes - l.lineStartRune
+			insertTruncator = truncated > 0 || l.config.TextContinues
+		}
+		if insertTruncator {
+			finalLine = append(finalLine, l.config.Truncator)
+		}
+	}
+
+	// Mark the paragraph as complete if needed.
+	if done {
+		l.more = false
+	}
+
+	return finalLine, truncated, done
+}
+
 // WrapNextLine wraps the shaped glyphs of a paragraph to a particular max width.
 // It is meant to be called iteratively to wrap each line, allowing lines to
 // be wrapped to different widths within the same paragraph. When done is true,
@@ -828,49 +877,11 @@ func (l *LineWrapper) WrapNextLine(maxWidth int) (finalLine Line, truncated int,
 	if !l.more {
 		return nil, 0, true
 	}
-	defer func() {
-		if len(finalLine) > 0 {
-			finalRun := finalLine[len(finalLine)-1]
-
-			// Zero trailing whitespace advance, to make room for the truncator
-			if L := len(finalRun.Glyphs); l.truncating && L != 0 {
-				if finalRun.Direction.IsVertical() {
-					if g := &finalRun.Glyphs[L-1]; g.Height == 0 {
-						g.YAdvance = 0
-					}
-				} else { // horizontal
-					if g := finalRun.Glyphs[L-1]; g.Width == 0 {
-						g.XAdvance = 0
-					}
-				}
-				finalRun.RecomputeAdvance()
-			}
-
-			// Update the start position of the next line.
-			l.lineStartRune = finalRun.Runes.Count + finalRun.Runes.Offset
-
-		}
 
-		// Check whether we've exhausted the text.
-		done = done || l.lineStartRune >= l.breaker.totalRunes
-		// Implement truncation if needed.
-		if l.truncating {
-			l.config.TruncateAfterLines--
-			insertTruncator := false
-			if l.config.TruncateAfterLines == 0 {
-				done = true
-				truncated = l.breaker.totalRunes - l.lineStartRune
-				insertTruncator = truncated > 0 || l.config.TextContinues
-			}
-			if insertTruncator {
-				finalLine = append(finalLine, l.config.Truncator)
-			}
-		}
-		// Mark the paragraph as complete if needed.
-		if done {
-			l.more = false
-		}
+	defer func() {
+		finalLine, truncated, done = l.postProcessLine(finalLine, done)
 	}()
+
 	// If the iterator is empty, return early.
 	_, firstRun, hasFirst := l.glyphRuns.Peek()
 	if !hasFirst {

diff --git a/shaping/wrapping_test.go b/shaping/wrapping_test.go
@@ -2772,14 +2772,14 @@ func TestLineWrapperBreakSpecific(t *testing.T) {
 				{
 					name:           "Always-Truncate",
 					config:         WrapConfig{BreakPolicy: Always, TruncateAfterLines: 1},
-					runeCounts:     []int{6},
-					truncatedCount: 6,
+					runeCounts:     []int{7},
+					truncatedCount: 5,
 				},
 				{
 					name:           "Never-Truncate",
 					config:         WrapConfig{BreakPolicy: Never, TruncateAfterLines: 1},
-					runeCounts:     []int{},
-					truncatedCount: 12,
+					runeCounts:     []int{7},
+					truncatedCount: 5,
 				},
 			},
 		},
@@ -2790,24 +2790,24 @@ func TestLineWrapperBreakSpecific(t *testing.T) {
 				{
 					name:       "WhenNecessary",
 					config:     WrapConfig{BreakPolicy: WhenNecessary},
-					runeCounts: []int{6, 6},
+					runeCounts: []int{7, 5},
 				},
 				{
 					name:           "WhenNecessary-Truncate",
 					config:         WrapConfig{BreakPolicy: WhenNecessary, TruncateAfterLines: 1},
-					runeCounts:     []int{6},
-					truncatedCount: 6,
+					runeCounts:     []int{7},
+					truncatedCount: 5,
 				},
 				{
 					name:       "Always",
 					config:     WrapConfig{BreakPolicy: Always},
-					runeCounts: []int{6, 6},
+					runeCounts: []int{7, 5},
 				},
 				{
 					name:           "Always-Truncate",
 					config:         WrapConfig{BreakPolicy: Always, TruncateAfterLines: 1},
-					runeCounts:     []int{6},
-					truncatedCount: 6,
+					runeCounts:     []int{7},
+					truncatedCount: 5,
 				},
 				{
 					name:       "Never",
@@ -2817,8 +2817,8 @@ func TestLineWrapperBreakSpecific(t *testing.T) {
 				{
 					name:           "Never-Truncate",
 					config:         WrapConfig{BreakPolicy: Never, TruncateAfterLines: 1},
-					runeCounts:     []int{},
-					truncatedCount: 12,
+					runeCounts:     []int{7},
+					truncatedCount: 5,
 				},
 			},
 		},
@@ -2886,12 +2886,12 @@ func TestLineWrapperBreakSpecific(t *testing.T) {
 				{
 					name:       "WhenNecessary",
 					config:     WrapConfig{BreakPolicy: WhenNecessary},
-					runeCounts: []int{1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1},
+					runeCounts: []int{1, 1, 2, 1, 2, 1, 1, 1, 1, 1},
 				},
 				{
 					name:       "Always",
 					config:     WrapConfig{BreakPolicy: Always},
-					runeCounts: []int{1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1},
+					runeCounts: []int{1, 1, 2, 1, 2, 1, 1, 1, 1, 1},
 				},
 				{
 					name:       "Never",
@@ -3209,7 +3209,7 @@ var regressionRuns = []Output{
 	},
 }
 
-func TestSpace(t *testing.T) {
+func TestTrailingSpace(t *testing.T) {
 	// assume single run, 1 to 1 rune <-> glyph mapping
 	shapedText := func(text []rune, line Line) string {
 		tu.Assert(t, len(line) == 1)