oh-my-opencode/src/tools/hashline-edit/diff-utils.test.ts

150 lines
4.4 KiB
TypeScript

/// <reference types="bun-types" />
import { describe, expect, it } from "bun:test"
import { parsePatch } from "diff"
import { generateUnifiedDiff } from "./diff-utils"
function createNumberedLines(totalLineCount: number): string {
return Array.from({ length: totalLineCount }, (_, index) => `line ${index + 1}`).join("\n")
}
describe("generateUnifiedDiff", () => {
describe("#given OpenCode compatibility format", () => {
it("#then includes the Index header emitted by diff library", () => {
//#given
const oldContent = "a\n"
const newContent = "b\n"
//#when
const diff = generateUnifiedDiff(oldContent, newContent, "test.ts")
//#then
expect(diff).toContain("Index: test.ts")
})
it("#then includes unified --- and +++ file headers", () => {
//#given
const oldContent = "a\n"
const newContent = "b\n"
//#when
const diff = generateUnifiedDiff(oldContent, newContent, "test.ts")
//#then
expect(diff).toContain("--- test.ts")
expect(diff).toContain("+++ test.ts")
})
it("#then remains parseable by OpenCode parsePatch flow", () => {
//#given
const oldContent = "line1\nline2\n"
const newContent = "line1\nline2-updated\n"
//#when
const diff = generateUnifiedDiff(oldContent, newContent, "test.ts")
const patches = parsePatch(diff)
//#then
expect(patches).toHaveLength(1)
expect(patches[0]?.oldFileName).toBe("test.ts")
expect(patches[0]?.newFileName).toBe("test.ts")
expect(patches[0]?.hunks).toHaveLength(1)
})
})
describe("#given content without trailing newline", () => {
it("#then keeps no-newline markers parseable", () => {
//#given
const oldContent = "a"
const newContent = "b"
//#when
const diff = generateUnifiedDiff(oldContent, newContent, "test.ts")
const patches = parsePatch(diff)
const hunkLines = patches[0]?.hunks[0]?.lines ?? []
//#then
expect(diff).toContain("\\ No newline at end of file")
expect(hunkLines).toEqual(["-a", "\\ No newline at end of file", "+b", "\\ No newline at end of file"])
})
})
it("creates separate hunks for distant changes", () => {
//#given
const oldContent = createNumberedLines(60)
const newLines = oldContent.split("\n")
newLines[4] = "line 5 updated"
newLines[49] = "line 50 updated"
const newContent = newLines.join("\n")
//#when
const diff = generateUnifiedDiff(oldContent, newContent, "sample.txt")
//#then
const hunkHeaders = diff.match(/^@@/gm) ?? []
expect(hunkHeaders.length).toBe(2)
})
it("creates a single hunk for adjacent changes", () => {
//#given
const oldContent = createNumberedLines(20)
const newLines = oldContent.split("\n")
newLines[9] = "line 10 updated"
newLines[10] = "line 11 updated"
const newContent = newLines.join("\n")
//#when
const diff = generateUnifiedDiff(oldContent, newContent, "sample.txt")
//#then
const hunkHeaders = diff.match(/^@@/gm) ?? []
expect(hunkHeaders.length).toBe(1)
expect(diff).toContain(" line 8")
expect(diff).toContain(" line 13")
})
it("limits each hunk to three context lines", () => {
//#given
const oldContent = createNumberedLines(20)
const newLines = oldContent.split("\n")
newLines[9] = "line 10 updated"
const newContent = newLines.join("\n")
//#when
const diff = generateUnifiedDiff(oldContent, newContent, "sample.txt")
//#then
expect(diff).toContain(" line 7")
expect(diff).toContain(" line 13")
expect(diff).not.toContain(" line 6")
expect(diff).not.toContain(" line 14")
})
it("returns a diff string for identical content", () => {
//#given
const oldContent = "alpha\nbeta\ngamma"
const newContent = "alpha\nbeta\ngamma"
//#when
const diff = generateUnifiedDiff(oldContent, newContent, "sample.txt")
//#then
expect(typeof diff).toBe("string")
expect(diff).toContain("--- sample.txt")
expect(diff).toContain("+++ sample.txt")
})
it("returns a valid diff when old content is empty", () => {
//#given
const oldContent = ""
const newContent = "first line\nsecond line"
//#when
const diff = generateUnifiedDiff(oldContent, newContent, "sample.txt")
//#then
expect(diff).toContain("--- sample.txt")
expect(diff).toContain("+++ sample.txt")
expect(diff).toContain("+first line")
})
})