fix(docs): render markdown strikethrough

CHANGELOG.md

@@ -10,6 +10,7 @@
 
 ### Fixed
 
+- Docs: render GFM `~~strikethrough~~` spans in the local markdown writer used by `docs write --tab --markdown`. (#702)
 - Docs: batch table-cell writes for `docs write --tab --markdown` to avoid per-cell Docs API quota bursts on table-heavy documents. (#699) — thanks @sebsnyk.
 - Gmail: preserve existing `gmail drafts update` attachments when `--attach` is omitted, add `--clear-attachments` for intentional removal, and keep `--attach` as explicit replacement. (#680, #681) — thanks @chrischall.
 

internal/cmd/docs_formatter.go

@@ -333,6 +333,10 @@ func buildTextStyleRequest(style TextStyle, baseOffset int64, tabID string) *doc
 		textStyle.Italic = true
 		fields = append(fields, "italic")
 	}
+	if style.Strikethrough {
+		textStyle.Strikethrough = true
+		fields = append(fields, "strikethrough")
+	}
 	if style.Code {
 		textStyle.WeightedFontFamily = &docs.WeightedFontFamily{
 			FontFamily: "Courier New",

internal/cmd/docs_formatter_test.go

@@ -43,6 +43,38 @@ func TestMarkdownToDocsRequests_TableStartIndexUsesBase(t *testing.T) {
 	}
 }
 
+func TestMarkdownToDocsRequests_Strikethrough(t *testing.T) {
+	elements := []MarkdownElement{{Type: MDParagraph, Content: "~~struck out~~ vs **bold**"}}
+	requests, text, tables := MarkdownToDocsRequests(elements, 10, "t.second")
+
+	if text != "struck out vs bold\n" {
+		t.Fatalf("unexpected text: %q", text)
+	}
+	if len(tables) != 0 {
+		t.Fatalf("unexpected tables: %d", len(tables))
+	}
+
+	var sawStrike bool
+	for _, req := range requests {
+		if req.UpdateTextStyle == nil || req.UpdateTextStyle.TextStyle == nil {
+			continue
+		}
+		if !req.UpdateTextStyle.TextStyle.Strikethrough {
+			continue
+		}
+		sawStrike = true
+		if req.UpdateTextStyle.Fields != "strikethrough" {
+			t.Fatalf("unexpected strikethrough fields: %q", req.UpdateTextStyle.Fields)
+		}
+		if got := req.UpdateTextStyle.Range; got.StartIndex != 10 || got.EndIndex != 20 || got.TabId != "t.second" {
+			t.Fatalf("unexpected strikethrough range: %#v", got)
+		}
+	}
+	if !sawStrike {
+		t.Fatalf("missing strikethrough request: %#v", requests)
+	}
+}
+
 // TestMarkdownToDocsRequests_AppendBulletsAndCode is a regression test for
 // #594. The append path used to inline literal "• " glyphs for bullet lists
 // (leaving paragraphs as NORMAL_TEXT) and split fenced code blocks into one

internal/cmd/docs_markdown.go

@@ -48,12 +48,13 @@ type MarkdownElement struct {
 
 // TextStyle represents text formatting
 type TextStyle struct {
-	Bold   bool
-	Italic bool
-	Code   bool
-	Link   string
-	Start  int64
-	End    int64
+	Bold          bool
+	Italic        bool
+	Strikethrough bool
+	Code          bool
+	Link          string
+	Start         int64
+	End           int64
 }
 
 // ParagraphStyle represents paragraph-level formatting
@@ -423,17 +424,18 @@ func parseInlineSegment(text string) (string, []TextStyle) {
 			}
 		}
 
-		if marker, bold, italic, ok := inlineMarkerAt(text, i); ok {
+		if marker, bold, italic, strikethrough, ok := inlineMarkerAt(text, i); ok {
 			searchFrom := i + len(marker)
 			if end := findClosingInlineMarker(text, searchFrom, marker); end >= 0 && end > searchFrom {
 				content, nestedStyles := parseInlineSegment(text[searchFrom:end])
 				start := utf16Len(stripped.String())
 				stripped.WriteString(content)
 				styles = append(styles, TextStyle{
-					Start:  start,
-					End:    start + utf16Len(content),
-					Bold:   bold,
-					Italic: italic,
+					Start:         start,
+					End:           start + utf16Len(content),
+					Bold:          bold,
+					Italic:        italic,
+					Strikethrough: strikethrough,
 				})
 				styles = appendShiftedStyles(styles, nestedStyles, start)
 				i = end + len(marker)
@@ -501,24 +503,41 @@ func appendShiftedStyles(styles []TextStyle, nested []TextStyle, offset int64) [
 	return styles
 }
 
-func inlineMarkerAt(text string, i int) (marker string, bold bool, italic bool, ok bool) {
-	for _, candidate := range []string{"***", "___", "**", "__", "*", "_"} {
+func inlineMarkerAt(text string, i int) (marker string, bold bool, italic bool, strikethrough bool, ok bool) {
+	for _, candidate := range []string{"***", "___", "**", "__", "~~", "*", "_"} {
 		if !strings.HasPrefix(text[i:], candidate) {
 			continue
 		}
 		if candidate[0] == '_' && !isUnderscoreOpeningDelimiter(text, i, len(candidate)) {
-			return "", false, false, false
+			return "", false, false, false, false
+		}
+		if candidate == "~~" {
+			if i > 0 && text[i-1] == '~' {
+				return "", false, false, false, false
+			}
+			if tildeRunLenAt(text, i) != len(candidate) {
+				return "", false, false, false, false
+			}
+			return candidate, false, false, true, true
 		}
 		switch len(candidate) {
 		case 3:
-			return candidate, true, true, true
+			return candidate, true, true, false, true
 		case 2:
-			return candidate, true, false, true
+			return candidate, true, false, false, true
 		default:
-			return candidate, false, true, true
+			return candidate, false, true, false, true
 		}
 	}
-	return "", false, false, false
+	return "", false, false, false, false
+}
+
+func tildeRunLenAt(text string, i int) int {
+	runEnd := i
+	for runEnd < len(text) && text[runEnd] == '~' {
+		runEnd++
+	}
+	return runEnd - i
 }
 
 func findClosingInlineMarker(text string, searchFrom int, marker string) int {
@@ -553,6 +572,9 @@ func closingInlineMarkerInRun(text string, searchFrom int, i int, marker string)
 	if runLen < markerLen {
 		return 0, runEnd, false
 	}
+	if marker == "~~" {
+		return i, runEnd, runLen == markerLen
+	}
 
 	if markerLen == 1 {
 		if runLen == 1 {

internal/cmd/docs_markdown_test.go

@@ -146,6 +146,27 @@ func TestParseInlineFormatting_NestedAndUnderscoreStyles(t *testing.T) {
 	assertInlineStyle(t, text, styles, "both", true, true, false)
 }
 
+func TestParseInlineFormatting_Strikethrough(t *testing.T) {
+	styles, text := ParseInlineFormatting("~~struck out~~ vs **bold**")
+	if text != "struck out vs bold" {
+		t.Fatalf("text = %q", text)
+	}
+
+	assertInlineStrikethrough(t, text, styles, "struck out")
+	assertInlineStyle(t, text, styles, "bold", true, false, false)
+}
+
+func TestParseInlineFormatting_LongTildeRunsAreLiteral(t *testing.T) {
+	styles, text := ParseInlineFormatting("~~ok~~ and ~~~not~~~ and ~~~~also not~~~~")
+	if text != "ok and ~~~not~~~ and ~~~~also not~~~~" {
+		t.Fatalf("text = %q", text)
+	}
+	if len(styles) != 1 {
+		t.Fatalf("expected only the exact two-tilde span to format, got %#v", styles)
+	}
+	assertInlineStrikethrough(t, text, styles, "ok")
+}
+
 func TestParseInlineFormatting_ClosingMarkerIgnoresCodeSpan(t *testing.T) {
 	styles, text := ParseInlineFormatting("**Use `**` marker** and _keep `_` literal_")
 	if text != "Use ** marker and keep _ literal" {
@@ -259,13 +280,26 @@ func assertInlineStyle(t *testing.T, text string, styles []TextStyle, wantText s
 		if int(style.End) > len(text) {
 			continue
 		}
-		if text[style.Start:style.End] == wantText && style.Bold == bold && style.Italic == italic && style.Code == code {
+		if text[style.Start:style.End] == wantText && style.Bold == bold && style.Italic == italic && style.Code == code && !style.Strikethrough {
 			return
 		}
 	}
 	t.Fatalf("missing style text=%q bold=%v italic=%v code=%v in %#v", wantText, bold, italic, code, styles)
 }
 
+func assertInlineStrikethrough(t *testing.T, text string, styles []TextStyle, wantText string) {
+	t.Helper()
+	for _, style := range styles {
+		if int(style.End) > len(text) {
+			continue
+		}
+		if text[style.Start:style.End] == wantText && style.Strikethrough {
+			return
+		}
+	}
+	t.Fatalf("missing strikethrough text=%q in %#v", wantText, styles)
+}
+
 func assertInlineLink(t *testing.T, text string, styles []TextStyle, wantText string, wantURL string) {
 	t.Helper()
 	for _, style := range styles {