Fix browser-like dash breaks in overlong runs

Prefer fitting hyphen-like breakpoints before emergency grapheme breaks in overlong breakable runs, while keeping keep-all behavior on the existing browser-matched path.

Refresh browser accuracy and benchmark snapshots.

Fixes #89

Author: chenglou

CHANGELOG.md

@@ -17,6 +17,7 @@
 - Line geometry now preserves browser-style terminal letter spacing, including rich-inline item boundaries and visible soft-hyphen breaks (#171).
 - Rich-inline item boundaries no longer overflow the requested width after a forced-progress break (#132).
 - The markdown chat demo now drops parsed link URLs unless they resolve to HTTP(S) hrefs (#168).
+- Overlong hyphenated runs now prefer browser-like dash breakpoints before falling back to emergency grapheme breaks (#89).
 
 ## 0.0.6 - 2026-04-22
 

accuracy/chrome.json

@@ -4,17 +4,17 @@
     "userAgent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/147.0.0.0 Safari/537.36",
     "devicePixelRatio": 2,
     "viewport": {
-      "innerWidth": 2560,
-      "innerHeight": 1227,
-      "outerWidth": 2560,
-      "outerHeight": 1314,
+      "innerWidth": 1512,
+      "innerHeight": 766,
+      "outerWidth": 1512,
+      "outerHeight": 853,
       "visualViewportScale": 1
     },
     "screen": {
-      "width": 2560,
-      "height": 1440,
-      "availWidth": 2560,
-      "availHeight": 1314,
+      "width": 1512,
+      "height": 982,
+      "availWidth": 1512,
+      "availHeight": 853,
       "colorDepth": 30,
       "pixelDepth": 30
     }
@@ -76825,5 +76825,5 @@
       "diff": 0
     }
   ],
-  "requestId": "1778234152524-g3ze5g"
+  "requestId": "1778455134064-dzaeth"
 }

accuracy/firefox.json

@@ -76825,5 +76825,5 @@
       "diff": 0
     }
   ],
-  "requestId": "1778234164610-4igphr"
+  "requestId": "1778455145984-0ujr0y"
 }

accuracy/safari.json

@@ -5,16 +5,16 @@
     "devicePixelRatio": 2,
     "viewport": {
       "innerWidth": 1440,
-      "innerHeight": 2440,
+      "innerHeight": 763,
       "outerWidth": 1440,
-      "outerHeight": 2530,
+      "outerHeight": 853,
       "visualViewportScale": 1
     },
     "screen": {
-      "width": 1440,
-      "height": 2560,
-      "availWidth": 1440,
-      "availHeight": 2530,
+      "width": 1512,
+      "height": 982,
+      "availWidth": 1512,
+      "availHeight": 853,
       "colorDepth": 24,
       "pixelDepth": 24
     }
@@ -76825,5 +76825,5 @@
       "diff": 0
     }
   ],
-  "requestId": "1778234157599-qh89bv"
+  "requestId": "1778455139711-8jiaqg"
 }

benchmarks/chrome.json

@@ -3,22 +3,22 @@
   "results": [
     {
       "label": "Our library: prepare()",
-      "ms": 18.100000023841858,
+      "ms": 17.75,
       "desc": "One cold 500-text measurement batch"
     },
     {
       "label": "Our library: layout()",
-      "ms": 0.14450000047683714,
+      "ms": 0.14424999952316286,
       "desc": "Normalized hot-path throughput per 500-text batch"
     },
     {
       "label": "DOM batch",
-      "ms": 3.850000023841858,
+      "ms": 3.9000000953674316,
       "desc": "Single 400→300px batch resize: write all, then read all"
     },
     {
       "label": "DOM interleaved",
-      "ms": 43.5,
+      "ms": 44.59999990463257,
       "desc": "Single 400→300px batch resize: write + read per div"
     }
   ],
@@ -30,7 +30,7 @@
     },
     {
       "label": "Our library: layoutWithLines()",
-      "ms": 0.053749996423721316,
+      "ms": 0.0550000011920929,
       "desc": "60-text shared-corpus batch across widths 180/220/260px; materializes text lines"
     },
     {
@@ -40,14 +40,14 @@
     },
     {
       "label": "Our library: layoutNextLine()",
-      "ms": 0.0449999988079071,
+      "ms": 0.04375,
       "desc": "60-text shared-corpus batch across widths 180/220/260px; streaming line-by-line layout"
     }
   ],
   "richInlineResults": [
     {
       "label": "Our library: measureRichInlineStats()",
-      "ms": 0.011250001192092896,
+      "ms": 0.010000002384185792,
       "desc": "36 rich-text inline flow shared-corpus texts across widths 180/220/260px; stats only"
     },
     {
@@ -62,14 +62,14 @@
     },
     {
       "label": "Our library: layoutNextRichInlineLineRange() + materializeRichInlineLineRange()",
-      "ms": 0.04250000119209289,
+      "ms": 0.04124999940395355,
       "desc": "36 rich-text inline flow shared-corpus texts across widths 180/220/260px; streaming range walk plus per-line materialization"
     }
   ],
   "richPreWrapResults": [
     {
       "label": "Our library: measureLineStats()",
-      "ms": 0.3049999952316284,
+      "ms": 0.3074999988079071,
       "desc": "12 generated pre-wrap texts with 320 hard-break chunks across widths 220/260/320px; stats only"
     },
     {
@@ -84,29 +84,29 @@
     },
     {
       "label": "Our library: layoutNextLine()",
-      "ms": 0.9475000023841857,
+      "ms": 0.9724999964237213,
       "desc": "12 generated pre-wrap texts with 320 hard-break chunks across widths 220/260/320px; streaming line-by-line layout"
     }
   ],
   "richLongResults": [
     {
       "label": "Our library: measureLineStats()",
-      "ms": 1.6537499994039535,
+      "ms": 1.6787499994039536,
       "desc": "8 Arabic long-form texts across widths 240/300/360px; stats only"
     },
     {
       "label": "Our library: layoutWithLines()",
-      "ms": 5.550000000000001,
+      "ms": 5.534999996423721,
       "desc": "8 Arabic long-form texts across widths 240/300/360px; materializes text lines"
     },
     {
       "label": "Our library: walkLineRanges()",
-      "ms": 2.208750000596046,
+      "ms": 2.23125,
       "desc": "8 Arabic long-form texts across widths 240/300/360px; line ranges only, no line text strings"
     },
     {
       "label": "Our library: layoutNextLine()",
-      "ms": 5.165000000596047,
+      "ms": 5.313749998807907,
       "desc": "8 Arabic long-form texts across widths 240/300/360px; streaming line-by-line layout"
     }
   ],
@@ -121,10 +121,10 @@
       "breakableSegments": 0,
       "width": 300,
       "lineCount": 193,
-      "analysisMs": 2.3999998569488525,
-      "measureMs": 4.1000001430511475,
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-      "layoutMs": 0.02600000023841858
+      "analysisMs": 2.5999999046325684,
+      "measureMs": 4.299999713897705,
+      "prepareMs": 6.800000190734863,
+      "layoutMs": 0.02649999976158142
     },
     {
       "id": "ja-rashomon",
@@ -136,10 +136,10 @@
       "breakableSegments": 1,
       "width": 300,
       "lineCount": 380,
-      "analysisMs": 4.700000047683716,
-      "measureMs": 7.900000333786011,
-      "prepareMs": 12.700000047683716,
-      "layoutMs": 0.04899999976158142
+      "analysisMs": 4.900000095367432,
+      "measureMs": 8.5,
+      "prepareMs": 13.600000143051147,
+      "layoutMs": 0.049000000953674315
     },
     {
       "id": "ko-unsu-joh-eun-nal",
@@ -151,10 +151,10 @@
       "breakableSegments": 0,
       "width": 300,
       "lineCount": 428,
-      "analysisMs": 3.3999998569488525,
-      "measureMs": 8.500000238418579,
-      "prepareMs": 11.900000095367432,
-      "layoutMs": 0.0775
+      "analysisMs": 3.4000000953674316,
+      "measureMs": 8.499999761581421,
+      "prepareMs": 12.200000047683716,
+      "layoutMs": 0.07850000023841858
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     {
       "id": "ko-sonagi",
@@ -166,10 +166,10 @@
       "breakableSegments": 2,
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       "lineCount": 332,
-      "analysisMs": 2.4000000953674316,
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+      "analysisMs": 2.5999999046325684,
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+      "prepareMs": 9.099999904632568,
+      "layoutMs": 0.05950000047683716
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     {
       "id": "zh-zhufu",
@@ -181,9 +181,9 @@
       "breakableSegments": 4,
       "width": 300,
       "lineCount": 626,
-      "analysisMs": 7.200000047683716,
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       "layoutMs": 0.08
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@@ -196,10 +196,10 @@
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       "id": "th-nithan-vetal-story-1",
@@ -211,10 +211,10 @@
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       "id": "my-cunning-heron-teacher",
@@ -226,10 +226,10 @@
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@@ -242,8 +242,8 @@
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@@ -256,10 +256,10 @@
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     {
       "id": "km-prachum-reuang-preng-khmer-volume-7-stories-1-10",
@@ -271,10 +271,10 @@
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     {
       "id": "hi-eidgah",
@@ -286,10 +286,10 @@
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       "id": "synthetic-long-breakable-runs",
@@ -301,10 +301,10 @@
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       "id": "ar-risalat-al-ghufran-part-1",
@@ -316,10 +316,10 @@
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   ]
 }