feat(core): add markdown table rendering support

packages/core/src/lib/index.ts

@@ -16,3 +16,4 @@ export * from "./tree-sitter"
 export * from "./data-paths"
 export * from "./extmarks"
 export * from "./terminal-palette"
+export * from "./table-renderer"

packages/core/src/lib/table-renderer.test.ts

@@ -0,0 +1,159 @@
+import { describe, it, expect } from "bun:test"
+import { getDisplayWidth, padToWidth, truncateToWidth, detectTableRanges, parseTable } from "./table-renderer"
+
+describe("getDisplayWidth", () => {
+  it("returns correct width for ASCII characters", () => {
+    expect(getDisplayWidth("hello")).toBe(5)
+    expect(getDisplayWidth("")).toBe(0)
+    expect(getDisplayWidth(" ")).toBe(1)
+  })
+
+  it("returns correct width for CJK characters", () => {
+    expect(getDisplayWidth("中文")).toBe(4)
+    expect(getDisplayWidth("日本語")).toBe(6)
+    expect(getDisplayWidth("한글")).toBe(4)
+  })
+
+  it("returns correct width for mixed content", () => {
+    expect(getDisplayWidth("Hello中文")).toBe(9)
+    expect(getDisplayWidth("abc日本語xyz")).toBe(12)
+  })
+
+  it("returns correct width for hiragana and katakana", () => {
+    expect(getDisplayWidth("あいう")).toBe(6)
+    expect(getDisplayWidth("アイウ")).toBe(6)
+  })
+})
+
+describe("padToWidth", () => {
+  it("pads left-aligned content", () => {
+    expect(padToWidth("hi", 5, "left")).toBe("hi   ")
+  })
+
+  it("pads right-aligned content", () => {
+    expect(padToWidth("hi", 5, "right")).toBe("   hi")
+  })
+
+  it("pads center-aligned content", () => {
+    expect(padToWidth("hi", 6, "center")).toBe("  hi  ")
+    expect(padToWidth("hi", 5, "center")).toBe(" hi  ")
+  })
+
+  it("returns original string when already at target width", () => {
+    expect(padToWidth("hello", 5, "left")).toBe("hello")
+  })
+
+  it("returns original string when exceeds target width", () => {
+    expect(padToWidth("hello", 3, "left")).toBe("hello")
+  })
+})
+
+describe("truncateToWidth", () => {
+  it("returns original string when within limit", () => {
+    expect(truncateToWidth("hello", 10)).toBe("hello")
+  })
+
+  it("truncates and adds ellipsis", () => {
+    expect(truncateToWidth("hello world", 8)).toBe("hello w…")
+  })
+
+  it("handles very short max width", () => {
+    expect(truncateToWidth("hello", 2)).toBe("he")
+  })
+
+  it("handles CJK characters correctly", () => {
+    const result = truncateToWidth("中文テスト", 6)
+    expect(getDisplayWidth(result)).toBeLessThanOrEqual(6)
+  })
+})
+
+describe("detectTableRanges", () => {
+  it("detects a simple table", () => {
+    const content = `Some text
+
+| A | B |
+|---|---|
+| 1 | 2 |
+
+More text`
+    const ranges = detectTableRanges(content, [])
+    expect(ranges.length).toBe(1)
+  })
+
+  it("detects multiple tables", () => {
+    const content = `| A | B |
+|---|---|
+| 1 | 2 |
+
+text
+
+| X | Y |
+|---|---|
+| 3 | 4 |`
+    const ranges = detectTableRanges(content, [])
+    expect(ranges.length).toBe(2)
+  })
+
+  it("ignores pipes in code blocks", () => {
+    const content = `\`\`\`
+| not | a | table |
+\`\`\``
+    const ranges = detectTableRanges(content, [])
+    expect(ranges.length).toBe(0)
+  })
+
+  it("requires delimiter row", () => {
+    const content = `| A | B |
+| 1 | 2 |`
+    const ranges = detectTableRanges(content, [])
+    expect(ranges.length).toBe(0)
+  })
+})
+
+describe("parseTable", () => {
+  it("parses a simple table", () => {
+    const content = `| Name | Age |
+|------|-----|
+| Alice | 30 |
+| Bob | 25 |`
+    const table = parseTable(content)
+    expect(table).not.toBeNull()
+    expect(table!.rows.length).toBe(4)
+    expect(table!.columnWidths.length).toBe(2)
+    expect(table!.columnAligns).toEqual(["left", "left"])
+  })
+
+  it("parses alignment markers", () => {
+    const content = `| Left | Center | Right |
+|:-----|:------:|------:|
+| a | b | c |`
+    const table = parseTable(content)
+    expect(table).not.toBeNull()
+    expect(table!.columnAligns).toEqual(["left", "center", "right"])
+  })
+
+  it("calculates column widths correctly", () => {
+    const content = `| Short | LongerColumn |
+|-------|--------------|
+| a | b |`
+    const table = parseTable(content)
+    expect(table).not.toBeNull()
+    expect(table!.columnWidths[0]).toBe(5)
+    expect(table!.columnWidths[1]).toBe(12)
+  })
+
+  it("handles CJK content width correctly", () => {
+    const content = `| Name | City |
+|------|------|
+| 田中 | 東京 |`
+    const table = parseTable(content)
+    expect(table).not.toBeNull()
+    expect(table!.columnWidths[0]).toBe(4)
+    expect(table!.columnWidths[1]).toBe(4)
+  })
+
+  it("returns null for invalid table", () => {
+    expect(parseTable("not a table")).toBeNull()
+    expect(parseTable("|---|")).toBeNull()
+  })
+})