refactor(hashline-edit): enforce three-op edit model

Unify internal hashline edit handling around replace/append/prepend to remove legacy operation shapes. This keeps normalization, ordering, deduplication, execution, and tests aligned with the new op/pos/end/lines contract.

src/tools/hashline-edit/edit-deduplication.ts

@@ -6,23 +6,13 @@ function normalizeEditPayload(payload: string | string[]): string {
 }
 
 function buildDedupeKey(edit: HashlineEdit): string {
-  switch (edit.type) {
+  switch (edit.op) {
-    case "set_line":
-      return `set_line|${edit.line}|${normalizeEditPayload(edit.text)}`
-    case "replace_lines":
-      return `replace_lines|${edit.start_line}|${edit.end_line}|${normalizeEditPayload(edit.text)}`
-    case "insert_after":
-      return `insert_after|${edit.line}|${normalizeEditPayload(edit.text)}`
-    case "insert_before":
-      return `insert_before|${edit.line}|${normalizeEditPayload(edit.text)}`
-    case "insert_between":
-      return `insert_between|${edit.after_line}|${edit.before_line}|${normalizeEditPayload(edit.text)}`
     case "replace":
-      return `replace|${edit.old_text}|${normalizeEditPayload(edit.new_text)}`
+      return `replace|${edit.pos}|${edit.end ?? ""}|${normalizeEditPayload(edit.lines)}`
     case "append":
-      return `append|${normalizeEditPayload(edit.text)}`
+      return `append|${edit.pos ?? ""}|${normalizeEditPayload(edit.lines)}`
     case "prepend":
-      return `prepend|${normalizeEditPayload(edit.text)}`
+      return `prepend|${edit.pos ?? ""}|${normalizeEditPayload(edit.lines)}`
     default:
       return JSON.stringify(edit)
   }

src/tools/hashline-edit/edit-operation-primitives.ts

@@ -150,11 +150,3 @@ export function applyPrepend(lines: string[], text: string | string[]): string[]
   }
   return [...normalized, ...lines]
 }
-
-export function applyReplace(content: string, oldText: string, newText: string | string[]): string {
-  if (!content.includes(oldText)) {
-    throw new Error(`Text not found: "${oldText}"`)
-  }
-  const replacement = Array.isArray(newText) ? newText.join("\n") : newText
-  return content.replaceAll(oldText, replacement)
-}

src/tools/hashline-edit/edit-operations.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, it } from "bun:test"
-import { applyHashlineEdits, applyInsertAfter, applyReplace, applyReplaceLines, applySetLine } from "./edit-operations"
+import { applyHashlineEdits, applyInsertAfter, applyReplaceLines, applySetLine } from "./edit-operations"
-import { applyAppend, applyPrepend } from "./edit-operation-primitives"
+import { applyAppend, applyInsertBetween, applyPrepend } from "./edit-operation-primitives"
 import { computeLineHash } from "./hash-computation"
 import type { HashlineEdit } from "./types"
 
@@ -49,7 +49,7 @@ describe("hashline edit operations", () => {
     //#when
     const result = applyHashlineEdits(
       lines.join("\n"),
-      [{ type: "insert_before", line: anchorFor(lines, 2), text: "before 2" }]
+      [{ op: "prepend", pos: anchorFor(lines, 2), lines: "before 2" }]
     )
 
     //#then
@@ -61,15 +61,7 @@ describe("hashline edit operations", () => {
     const lines = ["line 1", "line 2", "line 3"]
 
     //#when
-    const result = applyHashlineEdits(
+    const result = applyInsertBetween(lines, anchorFor(lines, 1), anchorFor(lines, 2), ["between"]).join("\n")
-      lines.join("\n"),
-      [{
-        type: "insert_between",
-        after_line: anchorFor(lines, 1),
-        before_line: anchorFor(lines, 2),
-        text: ["between"],
-      }]
-    )
 
     //#then
     expect(result).toEqual("line 1\nbetween\nline 2\nline 3")
@@ -89,7 +81,7 @@ describe("hashline edit operations", () => {
 
     //#when / #then
     expect(() =>
-      applyHashlineEdits(lines.join("\n"), [{ type: "insert_before", line: anchorFor(lines, 1), text: [] }])
+      applyHashlineEdits(lines.join("\n"), [{ op: "prepend", pos: anchorFor(lines, 1), lines: [] }])
     ).toThrow(/non-empty/i)
   })
 
@@ -98,28 +90,7 @@ describe("hashline edit operations", () => {
     const lines = ["line 1", "line 2"]
 
     //#when / #then
-    expect(() =>
+    expect(() => applyInsertBetween(lines, anchorFor(lines, 1), anchorFor(lines, 2), [])).toThrow(/non-empty/i)
-      applyHashlineEdits(
-        lines.join("\n"),
-        [{
-          type: "insert_between",
-          after_line: anchorFor(lines, 1),
-          before_line: anchorFor(lines, 2),
-          text: [],
-        }]
-      )
-    ).toThrow(/non-empty/i)
-  })
-
-  it("applies replace operation", () => {
-    //#given
-    const content = "hello world foo"
-
-    //#when
-    const result = applyReplace(content, "world", "universe")
-
-    //#then
-    expect(result).toEqual("hello universe foo")
   })
 
   it("applies mixed edits in one pass", () => {
@@ -127,8 +98,8 @@ describe("hashline edit operations", () => {
     const content = "line 1\nline 2\nline 3"
     const lines = content.split("\n")
     const edits: HashlineEdit[] = [
-      { type: "insert_after", line: anchorFor(lines, 1), text: "inserted" },
+      { op: "append", pos: anchorFor(lines, 1), lines: "inserted" },
-      { type: "set_line", line: anchorFor(lines, 3), text: "modified" },
+      { op: "replace", pos: anchorFor(lines, 3), lines: "modified" },
     ]
 
     //#when
@@ -143,8 +114,8 @@ describe("hashline edit operations", () => {
     const content = "line 1\nline 2"
     const lines = content.split("\n")
     const edits: HashlineEdit[] = [
-      { type: "insert_after", line: anchorFor(lines, 1), text: "inserted" },
+      { op: "append", pos: anchorFor(lines, 1), lines: "inserted" },
-      { type: "insert_after", line: anchorFor(lines, 1), text: "inserted" },
+      { op: "append", pos: anchorFor(lines, 1), lines: "inserted" },
     ]
 
     //#when
@@ -227,16 +198,9 @@ describe("hashline edit operations", () => {
     const lines = ["line 1", "line 2", "line 3"]
 
     //#when / #then
-    expect(() =>
+    expect(() => applyInsertBetween(lines, anchorFor(lines, 1), anchorFor(lines, 2), ["line 1", "line 2"])).toThrow(
-      applyHashlineEdits(lines.join("\n"), [
+      /non-empty/i
-        {
+    )
-          type: "insert_between",
-          after_line: anchorFor(lines, 1),
-          before_line: anchorFor(lines, 2),
-          text: ["line 1", "line 2"],
-        },
-      ])
-    ).toThrow(/non-empty/i)
   })
 
   it("restores indentation for first replace_lines entry", () => {
@@ -322,8 +286,8 @@ describe("hashline edit operations", () => {
 
     //#when
     const result = applyHashlineEdits(content, [
-      { type: "append", text: ["line 3"] },
+      { op: "append", lines: ["line 3"] },
-      { type: "prepend", text: ["line 0"] },
+      { op: "prepend", lines: ["line 0"] },
     ])
 
     //#then

src/tools/hashline-edit/edit-operations.ts

@@ -5,9 +5,7 @@ import {
   applyAppend,
   applyInsertAfter,
   applyInsertBefore,
-  applyInsertBetween,
   applyPrepend,
-  applyReplace,
   applyReplaceLines,
   applySetLine,
 } from "./edit-operation-primitives"
@@ -33,42 +31,17 @@ export function applyHashlineEditsWithReport(content: string, edits: HashlineEdi
 
   let noopEdits = 0
 
-  let result = content
+  let lines = content.length === 0 ? [] : content.split("\n")
-  let lines = result.length === 0 ? [] : result.split("\n")
 
   const refs = collectLineRefs(sortedEdits)
   validateLineRefs(lines, refs)
 
   for (const edit of sortedEdits) {
-    switch (edit.type) {
+    switch (edit.op) {
-      case "set_line": {
+      case "replace": {
-        lines = applySetLine(lines, edit.line, edit.text, { skipValidation: true })
+        const next = edit.end
-        break
+          ? applyReplaceLines(lines, edit.pos, edit.end, edit.lines, { skipValidation: true })
-      }
+          : applySetLine(lines, edit.pos, edit.lines, { skipValidation: true })
-      case "replace_lines": {
-        lines = applyReplaceLines(lines, edit.start_line, edit.end_line, edit.text, { skipValidation: true })
-        break
-      }
-      case "insert_after": {
-        const next = applyInsertAfter(lines, edit.line, edit.text, { skipValidation: true })
-        if (next.join("\n") === lines.join("\n")) {
-          noopEdits += 1
-          break
-        }
-        lines = next
-        break
-      }
-      case "insert_before": {
-        const next = applyInsertBefore(lines, edit.line, edit.text, { skipValidation: true })
-        if (next.join("\n") === lines.join("\n")) {
-          noopEdits += 1
-          break
-        }
-        lines = next
-        break
-      }
-      case "insert_between": {
-        const next = applyInsertBetween(lines, edit.after_line, edit.before_line, edit.text, { skipValidation: true })
         if (next.join("\n") === lines.join("\n")) {
           noopEdits += 1
           break
@@ -77,7 +50,9 @@ export function applyHashlineEditsWithReport(content: string, edits: HashlineEdi
         break
       }
       case "append": {
-        const next = applyAppend(lines, edit.text)
+        const next = edit.pos
+          ? applyInsertAfter(lines, edit.pos, edit.lines, { skipValidation: true })
+          : applyAppend(lines, edit.lines)
         if (next.join("\n") === lines.join("\n")) {
           noopEdits += 1
           break
@@ -86,7 +61,9 @@ export function applyHashlineEditsWithReport(content: string, edits: HashlineEdi
         break
       }
       case "prepend": {
-        const next = applyPrepend(lines, edit.text)
+        const next = edit.pos
+          ? applyInsertBefore(lines, edit.pos, edit.lines, { skipValidation: true })
+          : applyPrepend(lines, edit.lines)
         if (next.join("\n") === lines.join("\n")) {
           noopEdits += 1
           break
@@ -94,17 +71,6 @@ export function applyHashlineEditsWithReport(content: string, edits: HashlineEdi
         lines = next
         break
       }
-      case "replace": {
-        result = lines.join("\n")
-        const replaced = applyReplace(result, edit.old_text, edit.new_text)
-        if (replaced === result) {
-          noopEdits += 1
-          break
-        }
-        result = replaced
-        lines = result.split("\n")
-        break
-      }
     }
   }
 
@@ -124,6 +90,4 @@ export {
   applyReplaceLines,
   applyInsertAfter,
   applyInsertBefore,
-  applyInsertBetween,
-  applyReplace,
 } from "./edit-operation-primitives"

src/tools/hashline-edit/edit-ordering.ts

@@ -2,23 +2,13 @@ import { parseLineRef } from "./validation"
 import type { HashlineEdit } from "./types"
 
 export function getEditLineNumber(edit: HashlineEdit): number {
-  switch (edit.type) {
+  switch (edit.op) {
-    case "set_line":
-      return parseLineRef(edit.line).line
-    case "replace_lines":
-      return parseLineRef(edit.end_line).line
-    case "insert_after":
-      return parseLineRef(edit.line).line
-    case "insert_before":
-      return parseLineRef(edit.line).line
-    case "insert_between":
-      return parseLineRef(edit.before_line).line
-    case "append":
-      return Number.NEGATIVE_INFINITY
-    case "prepend":
-      return Number.NEGATIVE_INFINITY
     case "replace":
-      return Number.NEGATIVE_INFINITY
+      return parseLineRef(edit.end ?? edit.pos).line
+    case "append":
+      return edit.pos ? parseLineRef(edit.pos).line : Number.NEGATIVE_INFINITY
+    case "prepend":
+      return edit.pos ? parseLineRef(edit.pos).line : Number.NEGATIVE_INFINITY
     default:
       return Number.POSITIVE_INFINITY
   }
@@ -26,21 +16,12 @@ export function getEditLineNumber(edit: HashlineEdit): number {
 
 export function collectLineRefs(edits: HashlineEdit[]): string[] {
   return edits.flatMap((edit) => {
-    switch (edit.type) {
+    switch (edit.op) {
-      case "set_line":
+      case "replace":
-        return [edit.line]
+        return edit.end ? [edit.pos, edit.end] : [edit.pos]
-      case "replace_lines":
-        return [edit.start_line, edit.end_line]
-      case "insert_after":
-        return [edit.line]
-      case "insert_before":
-        return [edit.line]
-      case "insert_between":
-        return [edit.after_line, edit.before_line]
       case "append":
       case "prepend":
-      case "replace":
+        return edit.pos ? [edit.pos] : []
-        return []
       default:
         return []
     }

src/tools/hashline-edit/hashline-edit-executor.ts

@@ -32,7 +32,7 @@ function resolveToolCallID(ctx: ToolContextWithCallID): string | undefined {
 
 function canCreateFromMissingFile(edits: HashlineEdit[]): boolean {
   if (edits.length === 0) return false
-  return edits.every((edit) => edit.type === "append" || edit.type === "prepend")
+  return edits.every((edit) => edit.op === "append" || edit.op === "prepend")
 }
 
 function buildSuccessMeta(

src/tools/hashline-edit/index.ts

@@ -8,14 +8,9 @@ export {
 export { parseLineRef, validateLineRef } from "./validation"
 export type { LineRef } from "./validation"
 export type {
-  SetLine,
+  ReplaceEdit,
-  ReplaceLines,
+  AppendEdit,
-  InsertAfter,
+  PrependEdit,
-  InsertBefore,
-  InsertBetween,
-  Replace,
-  Append,
-  Prepend,
   HashlineEdit,
 } from "./types"
 export { NIBBLE_STR, HASHLINE_DICT, HASHLINE_REF_PATTERN, HASHLINE_OUTPUT_PATTERN } from "./constants"
@@ -23,8 +18,6 @@ export {
   applyHashlineEdits,
   applyInsertAfter,
   applyInsertBefore,
-  applyInsertBetween,
-  applyReplace,
   applyReplaceLines,
   applySetLine,
 } from "./edit-operations"

src/tools/hashline-edit/normalize-edits.test.ts

@@ -2,7 +2,7 @@ import { describe, expect, it } from "bun:test"
 import { normalizeHashlineEdits, type RawHashlineEdit } from "./normalize-edits"
 
 describe("normalizeHashlineEdits", () => {
-  it("maps replace with pos to set_line", () => {
+  it("maps replace with pos to replace", () => {
     //#given
     const input: RawHashlineEdit[] = [{ op: "replace", pos: "2#VK", lines: "updated" }]
 
@@ -10,10 +10,10 @@ describe("normalizeHashlineEdits", () => {
     const result = normalizeHashlineEdits(input)
 
     //#then
-    expect(result).toEqual([{ type: "set_line", line: "2#VK", text: "updated" }])
+    expect(result).toEqual([{ op: "replace", pos: "2#VK", lines: "updated" }])
   })
 
-  it("maps replace with pos and end to replace_lines", () => {
+  it("maps replace with pos and end to replace", () => {
     //#given
     const input: RawHashlineEdit[] = [{ op: "replace", pos: "2#VK", end: "4#MB", lines: ["a", "b"] }]
 
@@ -21,10 +21,10 @@ describe("normalizeHashlineEdits", () => {
     const result = normalizeHashlineEdits(input)
 
     //#then
-    expect(result).toEqual([{ type: "replace_lines", start_line: "2#VK", end_line: "4#MB", text: ["a", "b"] }])
+    expect(result).toEqual([{ op: "replace", pos: "2#VK", end: "4#MB", lines: ["a", "b"] }])
   })
 
-  it("maps anchored append and prepend to insert operations", () => {
+  it("maps anchored append and prepend preserving op", () => {
     //#given
     const input: RawHashlineEdit[] = [
       { op: "append", pos: "2#VK", lines: ["after"] },
@@ -35,10 +35,7 @@ describe("normalizeHashlineEdits", () => {
     const result = normalizeHashlineEdits(input)
 
     //#then
-    expect(result).toEqual([
+    expect(result).toEqual([{ op: "append", pos: "2#VK", lines: ["after"] }, { op: "prepend", pos: "4#MB", lines: ["before"] }])
-      { type: "insert_after", line: "2#VK", text: ["after"] },
-      { type: "insert_before", line: "4#MB", text: ["before"] },
-    ])
   })
 
   it("prefers pos over end for prepend anchors", () => {
@@ -49,7 +46,7 @@ describe("normalizeHashlineEdits", () => {
     const result = normalizeHashlineEdits(input)
 
     //#then
-    expect(result).toEqual([{ type: "insert_before", line: "3#AA", text: ["before"] }])
+    expect(result).toEqual([{ op: "prepend", pos: "3#AA", lines: ["before"] }])
   })
 
   it("rejects legacy payload without op", () => {

src/tools/hashline-edit/normalize-edits.ts

@@ -1,4 +1,4 @@
-import type { HashlineEdit } from "./types"
+import type { AppendEdit, HashlineEdit, PrependEdit, ReplaceEdit } from "./types"
 
 type HashlineToolOp = "replace" | "append" | "prepend"
 
@@ -36,62 +36,43 @@ function normalizeReplaceEdit(edit: RawHashlineEdit, index: number): HashlineEdi
   const pos = normalizeAnchor(edit.pos)
   const end = normalizeAnchor(edit.end)
   const anchor = requireLine(pos ?? end, index, "replace")
-  const text = requireLines(edit, index)
+  const lines = requireLines(edit, index)
 
-  if (pos && end) {
+  const normalized: ReplaceEdit = {
-    return {
+    op: "replace",
-      type: "replace_lines",
+    pos: anchor,
-      start_line: pos,
+    lines,
-      end_line: end,
-      text,
-    }
-  }
-
-  return {
-    type: "set_line",
-    line: anchor,
-    text,
   }
+  if (end) normalized.end = end
+  return normalized
 }
 
 function normalizeAppendEdit(edit: RawHashlineEdit, index: number): HashlineEdit {
   const pos = normalizeAnchor(edit.pos)
   const end = normalizeAnchor(edit.end)
   const anchor = pos ?? end
-  const text = requireLines(edit, index)
+  const lines = requireLines(edit, index)
 
-  if (!anchor) {
+  const normalized: AppendEdit = {
-    return {
+    op: "append",
-      type: "append",
+    lines,
-      text,
-    }
-  }
-
-  return {
-    type: "insert_after",
-    line: anchor,
-    text,
   }
+  if (anchor) normalized.pos = anchor
+  return normalized
 }
 
 function normalizePrependEdit(edit: RawHashlineEdit, index: number): HashlineEdit {
   const pos = normalizeAnchor(edit.pos)
   const end = normalizeAnchor(edit.end)
   const anchor = pos ?? end
-  const text = requireLines(edit, index)
+  const lines = requireLines(edit, index)
 
-  if (!anchor) {
+  const normalized: PrependEdit = {
-    return {
+    op: "prepend",
-      type: "prepend",
+    lines,
-      text,
-    }
-  }
-
-  return {
-    type: "insert_before",
-    line: anchor,
-    text,
   }
+  if (anchor) normalized.pos = anchor
+  return normalized
 }
 
 export function normalizeHashlineEdits(rawEdits: RawHashlineEdit[]): HashlineEdit[] {

src/tools/hashline-edit/types.ts

@@ -1,57 +1,20 @@
-export interface SetLine {
+export interface ReplaceEdit {
-  type: "set_line"
+  op: "replace"
-  line: string
+  pos: string
-  text: string | string[]
+  end?: string
+  lines: string | string[]
 }
 
-export interface ReplaceLines {
+export interface AppendEdit {
-  type: "replace_lines"
+  op: "append"
-  start_line: string
+  pos?: string
-  end_line: string
+  lines: string | string[]
-  text: string | string[]
 }
 
-export interface InsertAfter {
+export interface PrependEdit {
-  type: "insert_after"
+  op: "prepend"
-  line: string
+  pos?: string
-  text: string | string[]
+  lines: string | string[]
 }
 
-export interface InsertBefore {
+export type HashlineEdit = ReplaceEdit | AppendEdit | PrependEdit
-  type: "insert_before"
-  line: string
-  text: string | string[]
-}
-
-export interface InsertBetween {
-  type: "insert_between"
-  after_line: string
-  before_line: string
-  text: string | string[]
-}
-
-export interface Replace {
-  type: "replace"
-  old_text: string
-  new_text: string | string[]
-}
-
-export interface Append {
-  type: "append"
-  text: string | string[]
-}
-
-export interface Prepend {
-  type: "prepend"
-  text: string | string[]
-}
-
-export type HashlineEdit =
-  | SetLine
-  | ReplaceLines
-  | InsertAfter
-  | InsertBefore
-  | InsertBetween
-  | Replace
-  | Append
-  | Prepend