feat: selection-scoped edits with full-file context

README.md

@@ -31,6 +31,7 @@ The main difference between jumpy and other tools, like 99, are:
 #
 
 - **inline prompt**: describe a change without leaving the buffer
+- **selection-scoped edits**: visually select a function (or any region) and prompt — the whole buffer is still sent as context so the model understands the surroundings, while it focuses on your selection
 - **multi-line prompt + history**: `<C-CR>` submits, `<CR>` adds a newline, `<Up>`/`<Down>` recall earlier prompts
 - **async & parallel prompts**: requests run in the background; each response lands in its own buffer (`:JumpyCancel` aborts everything in flight)
 - **multi-file prompts**: `@mention` several files in one prompt and review the cross-file hunks

lua/jumpy/init.lua

@@ -130,7 +130,6 @@ function M._setup_highlights()
   hl(0, "JumpyRemoved", { bg = "#3a1a1a", strikethrough = true, default = true })
   hl(0, "JumpyAddedSign", { fg = "#4ec94e", default = true })
   hl(0, "JumpyRemovedSign", { fg = "#e05252", default = true })
-  -- Inspect overlay: a read-only, yellow before/after view of a recorded hunk.
   hl(0, "JumpyInspect", { bg = "#3a3320", default = true })
   hl(0, "JumpyInspectSign", { fg = "#d7b95a", default = true })
   hl(0, "JumpyInspectOther", { fg = "#8a7a3a", italic = true, default = true })
@@ -149,8 +148,10 @@ function M._setup_keymaps()
   local opts = { silent = true }
   local c = M.config.keymaps
 
+  -- The prompt is also bound in visual mode ("x") so you can select a region
+  -- and scope the edit to it; everything else is normal-mode only.
   local keymaps = {
-    { c.prompt, "jumpy.prompt", "open" },
+    { c.prompt, "jumpy.prompt", "open", { "n", "x" } },
     { c.next_hunk, "jumpy.navigate", "next_hunk" },
     { c.prev_hunk, "jumpy.navigate", "prev_hunk" },
     { c.accept, "jumpy.navigate", "accept" },
@@ -163,8 +164,8 @@ function M._setup_keymaps()
   }
 
   for _, km in ipairs(keymaps) do
-    local key, mod, fn = km[1], km[2], km[3]
-    map("n", key, function()
+    local key, mod, fn, modes = km[1], km[2], km[3], km[4] or "n"
+    map(modes, key, function()
       require(mod)[fn]()
     end, opts)
   end

lua/jumpy/llm.lua

@@ -36,11 +36,29 @@ local function build_messages(context)
     }
   end
 
+  -- A visual selection marks the region to focus on. The full file is still
+  -- sent for context; the model is asked to prefer changing only the selection.
+  local selection_note = ""
+  local sel = context.selection
+  if sel and sel.lines and #sel.lines > 0 then
+    selection_note = string.format(
+      "\n\nFocus on the SELECTED region below (lines %d-%d). Use the rest of the "
+        .. "file as context and prefer to change only the selection:\n"
+        .. "--- SELECTION (lines %d-%d) ---\n%s\n--- END SELECTION ---",
+      sel.start_line or 0,
+      sel.end_line or 0,
+      sel.start_line or 0,
+      sel.end_line or 0,
+      table.concat(sel.lines, "\n")
+    )
+  end
+
   local user_content = string.format(
-    "File type: %s\n\n--- FILE CONTENTS ---\n%s\n--- END FILE ---%s\n\nInstruction: %s",
+    "File type: %s\n\n--- FILE CONTENTS ---\n%s\n--- END FILE ---%s%s\n\nInstruction: %s",
     context.filetype or "text",
     context.file_contents,
     context.symbols,
+    selection_note,
     context.prompt
   )
 

lua/jumpy/prompt.lua

@@ -399,8 +399,18 @@ function M._submit()
   local source_buf = state.source_buf
   local visual_selection = state.visual_selection
 
-  local source_lines = visual_selection and vim.split(visual_selection.text, "\n", { plain = true })
-    or vim.api.nvim_buf_get_lines(source_buf, 0, -1, false)
+  -- Always send the whole buffer so the model has surrounding context; a visual
+  -- selection just marks the region to focus on (see `selection` in the context
+  -- and jumpy.llm). Edits are patched against the full buffer.
+  local source_lines = vim.api.nvim_buf_get_lines(source_buf, 0, -1, false)
+
+  local selection = visual_selection
+      and {
+        start_line = visual_selection.start_line,
+        end_line = visual_selection.end_line,
+        lines = vim.split(visual_selection.text, "\n", { plain = true }),
+      }
+    or nil
 
   local source_name = vim.api.nvim_buf_get_name(source_buf)
   local source_rel = source_name ~= "" and path.rel_path(source_name, path.project_root()) or "current"
@@ -582,6 +592,7 @@ function M._submit()
         prompt = cleaned_prompt,
         symbols = symbols,
         filetype = filetype,
+        selection = selection,
       }
 
       llm.request(context, function(response_text)
@@ -595,10 +606,10 @@ function M._submit()
           local render = require("jumpy.render")
           local patch = require("jumpy.patch")
 
-          -- Full-buffer prompts re-read the buffer so parallel work done in
-          -- the meantime is respected; visual-selection prompts keep the
-          -- snapshot since they target a fixed region.
-          local original = visual_selection and source_lines or vim.api.nvim_buf_get_lines(source_buf, 0, -1, false)
+          -- Re-read the buffer so parallel work done while the request was in
+          -- flight is respected. A selection only guided the model; the patch
+          -- and resulting hunks are computed against the whole buffer.
+          local original = vim.api.nvim_buf_get_lines(source_buf, 0, -1, false)
 
           local proposed_lines, unmatched = patch.apply(original, response_text)
 
@@ -607,13 +618,6 @@ function M._submit()
           end
 
           local hunks = diff.compute(original, proposed_lines)
-          if visual_selection then
-            local offset = visual_selection.start_line - 1
-
-            for _, hunk in ipairs(hunks) do
-              hunk.old_start = hunk.old_start + offset
-            end
-          end
 
           if #hunks == 0 then
             vim.notify("jumpy: no changes proposed", vim.log.levels.INFO)

tests/llm_spec.lua

@@ -55,6 +55,42 @@ describe("llm Claude Code command", function()
   end)
 end)
 
+describe("llm single-file selection", function()
+  it("sends the whole file plus a marked selection region", function()
+    local msgs = llm._build_messages({
+      filetype = "lua",
+      file_contents = "local a = 1\nlocal b = 2\nlocal c = 3",
+      symbols = "",
+      prompt = "rename b",
+      selection = {
+        start_line = 2,
+        end_line = 2,
+        lines = { "local b = 2" },
+      },
+    })
+
+    local user = msgs[2].content
+    -- full file is present as context
+    assert.is_truthy(user:find("local a = 1", 1, true))
+    assert.is_truthy(user:find("local c = 3", 1, true))
+    -- the selection is called out with its line range
+    assert.is_truthy(user:find("--- SELECTION (lines 2-2) ---", 1, true))
+    assert.is_truthy(user:find("Focus on the SELECTED region", 1, true))
+    assert.is_truthy(user:find("Instruction: rename b", 1, true))
+  end)
+
+  it("omits the selection note when there is no selection", function()
+    local msgs = llm._build_messages({
+      filetype = "lua",
+      file_contents = "local a = 1",
+      symbols = "",
+      prompt = "do it",
+    })
+
+    assert.is_nil(msgs[2].content:find("SELECTION", 1, true))
+  end)
+end)
+
 describe("llm multi-file messages", function()
   it("names the current file so relative references resolve", function()
     local msgs = llm._build_messages({