feat(core): add embedded v2 session runtime and tool foundation (#30632)

packages/core/test/patch.test.ts

@@ -0,0 +1,57 @@
+import { describe, expect, test } from "bun:test"
+import { Patch } from "@opencode-ai/core/patch"
+
+describe("Patch", () => {
+  test("parses add, update, and delete hunks", () => {
+    expect(
+      Patch.parse("*** Begin Patch\n*** Add File: add.txt\n+added\n*** Update File: update.txt\n@@ section\n-old\n+new\n*** Delete File: delete.txt\n*** End Patch"),
+    ).toEqual([
+      { type: "add", path: "add.txt", contents: "added" },
+      { type: "update", path: "update.txt", chunks: [{ oldLines: ["old"], newLines: ["new"], changeContext: "section", endOfFile: undefined }], movePath: undefined },
+      { type: "delete", path: "delete.txt" },
+    ])
+  })
+
+  test("strips a heredoc wrapper", () => {
+    expect(Patch.parse("cat <<'EOF'\n*** Begin Patch\n*** Add File: add.txt\n+added\n*** End Patch\nEOF")).toEqual([
+      { type: "add", path: "add.txt", contents: "added" },
+    ])
+  })
+
+  test("derives fuzzy line updates while preserving BOM", () => {
+    const update = Patch.derive(
+      "update.txt",
+      [{ oldLines: ["  old   "], newLines: ["new"] }],
+      "\uFEFFold\n",
+    )
+    expect(update).toEqual({ content: "new\n", bom: true })
+    expect(Patch.joinBom(update.content, update.bom)).toBe("\uFEFFnew\n")
+  })
+
+  test("matches EOF-anchored chunks from the end", () => {
+    expect(
+      Patch.derive(
+        "update.txt",
+        [{ oldLines: ["marker", "end"], newLines: ["marker changed", "end"], endOfFile: true }],
+        "marker\nmiddle\nmarker\nend\n",
+      ).content,
+    ).toBe("marker\nmiddle\nmarker changed\nend\n")
+  })
+
+  test("parses the EOF marker inside update chunks", () => {
+    expect(Patch.parse("*** Begin Patch\n*** Update File: update.txt\n@@\n-last\n+end\n*** End of File\n*** End Patch")).toEqual([
+      {
+        type: "update",
+        path: "update.txt",
+        movePath: undefined,
+        chunks: [{ oldLines: ["last"], newLines: ["end"], changeContext: undefined, endOfFile: true }],
+      },
+    ])
+  })
+
+  test("rejects malformed hunk bodies", () => {
+    expect(() => Patch.parse("*** Begin Patch\n*** Add File: add.txt\nmissing plus\n*** End Patch")).toThrow("Invalid add file line")
+    expect(() => Patch.parse("*** Begin Patch\n*** Update File: update.txt\n*** End Patch")).toThrow("expected at least one @@ chunk")
+    expect(() => Patch.parse("*** Begin Patch\n*** Delete File: delete.txt\nunexpected body\n*** End Patch")).toThrow("Invalid patch line")
+  })
+})