feat: support vim single-character replace

Author: reobin

packages/opencode/src/cli/cmd/tui/component/vim/vim-handler.ts

@@ -48,6 +48,7 @@ import {
   previousParagraphOperation,
   prevWordStart,
   replaceUnderCursor,
+  replaceSelection,
   substituteLine,
   substituteLineEnd,
   syncSelection,
@@ -123,6 +124,12 @@ export function createVimHandler(input: {
     return event.name ?? ""
   }
 
+  function replaceValue(event: VimEvent, visual = false) {
+    if (event.name === "return") return visual ? "\r" : "\n"
+    if (isPrintable(event)) return value(event)
+    return null
+  }
+
   function isShifted(event: VimEvent, key: string) {
     return event.name === key.toUpperCase() || (event.name === key && !!event.shift)
   }
@@ -259,6 +266,55 @@ export function createVimHandler(input: {
   function dispatch(event: VimEvent, key: string): boolean {
     if (!preservesWantedColumn(event, key)) clearWantedColumn()
 
+    if (input.state.pending() === "r") {
+      if (hasModifier(event)) {
+        input.state.clearPending()
+        return false
+      }
+
+      const next = replaceValue(event)
+      if (next !== null) {
+        edit(() => {
+          const offset = input.textarea().cursorOffset
+          const reg = deleteUnderCursor(input.textarea())
+          if (reg) {
+            input.textarea().insertText(next)
+            input.textarea().cursorOffset = next === "\n" ? offset + 1 : offset
+          }
+          input.state.clearPending()
+        })
+        event.preventDefault()
+        return true
+      }
+
+      input.state.clearPending()
+      event.preventDefault()
+      return true
+    }
+
+    if (input.state.pending() === "vr" && input.state.isVisual()) {
+      if (hasModifier(event)) {
+        input.state.clearPending()
+        return false
+      }
+
+      const next = replaceValue(event, true)
+      if (next !== null) {
+        edit(() => {
+          replaceSelection(input.textarea(), next, input.state.isVisualLine(), input.state.anchor() ?? undefined)
+          clearSelection(input.textarea())
+          input.state.clearPending()
+          input.state.setMode("normal")
+        })
+        event.preventDefault()
+        return true
+      }
+
+      input.state.clearPending()
+      event.preventDefault()
+      return true
+    }
+
     const scroll = vimScroll(event)
     if (scroll) {
       input.state.clearPending()
@@ -316,6 +372,12 @@ export function createVimHandler(input: {
         return true
       }
 
+      if (key === "r" && !event.shift && !hasModifier(event)) {
+        input.state.setPending("vr")
+        event.preventDefault()
+        return true
+      }
+
       if ((key === "i" || key === "a" || key === "o") && !event.shift && !hasModifier(event)) {
         event.preventDefault()
         return true
@@ -659,6 +721,12 @@ export function createVimHandler(input: {
       return true
     }
 
+    if (key === "r" && !event.shift && !hasModifier(event)) {
+      input.state.setPending("r")
+      event.preventDefault()
+      return true
+    }
+
     if (key === "p" && !event.shift && !hasModifier(event)) {
       edit(() => {
         pasteAfter(input.textarea(), register())

packages/opencode/src/cli/cmd/tui/component/vim/vim-motions.ts

@@ -832,6 +832,19 @@ export function toggleSelectionCase(textarea: TextareaRenderable, linewise = fal
   textarea.cursorOffset = sel.start
 }
 
+export function replaceSelection(textarea: TextareaRenderable, value: string, linewise = false, anchor?: number) {
+  const sel = selectionRange(textarea, anchor, linewise)
+  if (!sel) return
+  const next = textarea.plainText
+    .slice(sel.start, sel.end)
+    .split("")
+    .map((char) => (char === "\n" ? char : value))
+    .join("")
+  deleteOffsets(textarea, sel.start, sel.end)
+  textarea.insertText(next)
+  textarea.cursorOffset = sel.start
+}
+
 export function deleteSelection(textarea: TextareaRenderable, linewise = false, anchor?: number): VimRegister {
   const sel = selectionRange(textarea, anchor, linewise)
   if (!sel) return null

packages/opencode/src/cli/cmd/tui/component/vim/vim-state.ts

@@ -1,7 +1,7 @@
 import { createEffect, createMemo, createSignal, type Accessor } from "solid-js"
 
 export type VimMode = "normal" | "insert" | "replace" | "visual" | "visual-line" | "copy"
-export type VimPending = "" | "c" | "d" | "g" | "z" | "f" | "F" | "t" | "T" | "y"
+export type VimPending = "" | "c" | "d" | "g" | "z" | "f" | "F" | "t" | "T" | "y" | "r" | "vr"
 export type VimFind = { char: string; forward: boolean; till: boolean } | null
 export type VimRegister = { text: string; linewise: boolean } | null
 export type VimSnapshot = { text: string; cursor: number; data?: unknown }

packages/opencode/test/cli/tui/vim-motions.test.ts

@@ -166,7 +166,7 @@ function createHandler(
   const [mode, setMode] = createSignal<"normal" | "insert" | "replace" | "visual" | "visual-line" | "copy">(
     options?.mode ?? "normal",
   )
-  const [pending, setPending] = createSignal<"" | "c" | "d" | "g" | "z" | "f" | "F" | "t" | "T" | "y">("")
+  const [pending, setPending] = createSignal<"" | "c" | "d" | "g" | "z" | "f" | "F" | "t" | "T" | "y" | "r" | "vr">("")
   const [lastFind, setLastFind] = createSignal<{ char: string; forward: boolean; till: boolean } | null>(null)
   const [register, setRegister] = createSignal<{ text: string; linewise: boolean } | null>(null)
   const [anchor, setAnchor] = createSignal<number | null>(null)
@@ -1565,6 +1565,72 @@ describe("vim motion handler", () => {
     expect(ctx.textarea.cursorOffset).toBe(0)
   })
 
+  test("r replaces one character and stays normal", () => {
+    const ctx = createHandler("abcd")
+    ctx.textarea.cursorOffset = 1
+
+    const start = createEvent("r")
+    expect(ctx.handler.handleKey(start.event)).toBe(true)
+    expect(start.prevented()).toBe(true)
+    expect(ctx.state.pending()).toBe("r")
+
+    const replacement = createEvent("X")
+    expect(ctx.handler.handleKey(replacement.event)).toBe(true)
+    expect(replacement.prevented()).toBe(true)
+    expect(ctx.textarea.plainText).toBe("aXcd")
+    expect(ctx.textarea.cursorOffset).toBe(1)
+    expect(ctx.state.mode()).toBe("normal")
+    expect(ctx.state.pending()).toBe("")
+  })
+
+  test("r replaces with space", () => {
+    const ctx = createHandler("abcd")
+    ctx.textarea.cursorOffset = 2
+
+    ctx.handler.handleKey(createEvent("r").event)
+    ctx.handler.handleKey(createEvent("space").event)
+
+    expect(ctx.textarea.plainText).toBe("ab d")
+    expect(ctx.textarea.cursorOffset).toBe(2)
+    expect(ctx.state.mode()).toBe("normal")
+  })
+
+  test("r return replaces character with newline and moves to next line", () => {
+    const ctx = createHandler("abcd")
+    ctx.textarea.cursorOffset = 1
+
+    ctx.handler.handleKey(createEvent("r").event)
+    ctx.handler.handleKey(createEvent("return").event)
+
+    expect(ctx.textarea.plainText).toBe("a\ncd")
+    expect(ctx.textarea.cursorOffset).toBe(2)
+    expect(ctx.state.mode()).toBe("normal")
+  })
+
+  test("r does not insert on empty line", () => {
+    const ctx = createHandler("ab\n\ncd")
+    ctx.textarea.cursorOffset = 3
+
+    ctx.handler.handleKey(createEvent("r").event)
+    ctx.handler.handleKey(createEvent("X").event)
+
+    expect(ctx.textarea.plainText).toBe("ab\n\ncd")
+    expect(ctx.textarea.cursorOffset).toBe(3)
+    expect(ctx.state.pending()).toBe("")
+  })
+
+  test("r replaces with uppercase characters before jump handling", () => {
+    const ctx = createHandler("abcd")
+    ctx.textarea.cursorOffset = 1
+
+    ctx.handler.handleKey(createEvent("r").event)
+    ctx.handler.handleKey(createEvent("G").event)
+
+    expect(ctx.textarea.plainText).toBe("aGcd")
+    expect(ctx.textarea.cursorOffset).toBe(1)
+    expect(ctx.jumpCalls).toEqual([])
+  })
+
   test("R enters replace mode and escape exits", () => {
     const ctx = createHandler("abc")
 
@@ -3451,6 +3517,35 @@ describe("vim motion handler", () => {
     expect((ctx.textarea as any).editorView.getSelection()).toBe(null)
   })
 
+  test("visual r replaces selection before jump handling", () => {
+    const ctx = createHandler("abcd\nefgh")
+    ctx.textarea.cursorOffset = 1
+
+    ctx.handler.handleKey(createEvent("v").event)
+    ctx.handler.handleKey(createEvent("l").event)
+    ctx.handler.handleKey(createEvent("r").event)
+    ctx.handler.handleKey(createEvent("G").event)
+
+    expect(ctx.textarea.plainText).toBe("aGGd\nefgh")
+    expect(ctx.textarea.cursorOffset).toBe(1)
+    expect(ctx.jumpCalls).toEqual([])
+    expect(ctx.state.mode()).toBe("normal")
+  })
+
+  test("visual r return inserts carriage returns without splitting lines", () => {
+    const ctx = createHandler("abcd")
+    ctx.textarea.cursorOffset = 1
+
+    ctx.handler.handleKey(createEvent("v").event)
+    ctx.handler.handleKey(createEvent("l").event)
+    ctx.handler.handleKey(createEvent("r").event)
+    ctx.handler.handleKey(createEvent("return").event)
+
+    expect(ctx.textarea.plainText).toBe("a\r\rd")
+    expect(ctx.textarea.cursorOffset).toBe(1)
+    expect(ctx.state.mode()).toBe("normal")
+  })
+
   test("visual mode with backward motion", () => {
     const ctx = createHandler("hello world")
     ctx.textarea.cursorOffset = 5
@@ -5140,7 +5235,7 @@ describe("copy mode cursor state", () => {
     const textarea = createTextarea("")
     const [enabled] = createSignal(true)
     const [mode, setMode] = createSignal<"normal" | "insert" | "replace" | "visual" | "visual-line" | "copy">("copy")
-    const [pending, setPending] = createSignal<"" | "c" | "d" | "g" | "z" | "f" | "F" | "t" | "T" | "y">("")
+    const [pending, setPending] = createSignal<"" | "c" | "d" | "g" | "z" | "f" | "F" | "t" | "T" | "y" | "r" | "vr">("")
     const [lastFind, setLastFind] = createSignal<{ char: string; forward: boolean; till: boolean } | null>(null)
     const [register, setRegister] = createSignal<{ text: string; linewise: boolean } | null>(null)
     const [anchor, setAnchor] = createSignal<number | null>(null)