feat(core): require Neovim 0.12

Raise the minimum supported Neovim version to 0.12 and update
the health check and docs to match the new baseline. Also align
Tree-sitter parser checks with the Neovim 0.12 get_parser()
contract and keep invalid buffers guarded before parser lookup.

Author: mhiro2

README.md

@@ -40,7 +40,7 @@ peekstack.nvim focuses on preserving the _trail_ of your exploration.
 
 ## 📦 Requirements
 
-- Neovim ≥ 0.10
+- Neovim ≥ 0.12
 - `rg` (only if you use `grep.search`)
 - Optional: `telescope.nvim` / `fzf-lua` / `snacks.nvim` (if you switch picker backends)
 - Optional: Tree-sitter parsers (for `ui.title.context` and stack view preview syntax highlighting; Neovim bundles the runtime, but parsers are separate)

doc/peekstack.txt

@@ -9,7 +9,7 @@ peekstack.nvim provides a peek stack UI for LSP, diagnostics, files, marks,
 and grep results. Pop open floating windows that stack visually, navigate
 between them, promote to splits, and optionally persist sessions.
 
-Requires Neovim >= 0.10.
+Requires Neovim >= 0.12.
 
 ==============================================================================
 SETUP                                                      *peekstack-setup*
@@ -580,7 +580,7 @@ Other highlights:
 HEALTH                                                   *peekstack-health*
 
 Run `:checkhealth peekstack` to verify requirements:
-- Neovim >= 0.10
+- Neovim >= 0.12
 - `rg` executable (optional, for grep.search)
 - Configured picker backend availability (telescope / fzf-lua / snacks)
 - Persist setup and git repository detection

lua/peekstack/health.lua

@@ -10,10 +10,10 @@ local PICKER_MODULES = {
 function M.check()
   vim.health.start("peekstack")
 
-  if vim.fn.has("nvim-0.10") == 1 then
-    vim.health.ok("nvim >= 0.10")
+  if vim.fn.has("nvim-0.12") == 1 then
+    vim.health.ok("nvim >= 0.12")
   else
-    vim.health.error("nvim >= 0.10 is required (vim.lsp.get_clients, vim.islist, vim.system)")
+    vim.health.error("nvim >= 0.12 is required")
   end
 
   if vim.fn.executable("rg") == 1 then
@@ -62,8 +62,8 @@ function M.check()
   -- Tree-sitter context
   local title = cfg.ui and cfg.ui.title
   if title and title.context and title.context.enabled then
-    local ts_ok = pcall(vim.treesitter.get_parser, 0)
-    if ts_ok then
+    local parser = vim.treesitter.get_parser(0)
+    if parser then
       vim.health.ok("tree-sitter context enabled (parser available for current buffer)")
     else
       vim.health.info("tree-sitter context enabled but no parser for the current buffer filetype")

lua/peekstack/util/treesitter.lua

@@ -29,9 +29,13 @@ function M.context_at(bufnr, line, col, opts)
     return nil
   end
 
-  -- Check if parser is available
-  local ok, parser = pcall(vim.treesitter.get_parser, bufnr)
-  if not ok or not parser then
+  if bufnr ~= 0 and not vim.api.nvim_buf_is_valid(bufnr) then
+    return nil
+  end
+
+  -- Nvim 0.12+ returns nil when a parser cannot be created.
+  local parser = vim.treesitter.get_parser(bufnr)
+  if not parser then
     return nil
   end
 

tests/health_spec.lua

@@ -9,6 +9,7 @@ describe("peekstack.health", function()
   local original_health_info
   local original_executable
   local original_has
+  local original_get_parser
 
   ---@type string[]
   local messages
@@ -22,6 +23,7 @@ describe("peekstack.health", function()
     original_health_info = vim.health.info
     original_executable = vim.fn.executable
     original_has = vim.fn.has
+    original_get_parser = vim.treesitter.get_parser
 
     vim.health.start = function() end
     vim.health.ok = function(msg)
@@ -46,6 +48,7 @@ describe("peekstack.health", function()
     vim.health.info = original_health_info
     vim.fn.executable = original_executable
     vim.fn.has = original_has
+    vim.treesitter.get_parser = original_get_parser
     config.setup({})
   end)
 
@@ -60,7 +63,7 @@ describe("peekstack.health", function()
 
     health.check()
 
-    assert.is_true(vim.list_contains(messages, "ok:nvim >= 0.10"))
+    assert.is_true(vim.list_contains(messages, "ok:nvim >= 0.12"))
     assert.is_true(vim.list_contains(messages, "ok:rg available"))
   end)
 
@@ -123,4 +126,31 @@ describe("peekstack.health", function()
     end
     assert.is_true(found_persist)
   end)
+
+  it("reports tree-sitter info when context is enabled without a parser", function()
+    vim.fn.has = function()
+      return 1
+    end
+    vim.fn.executable = function()
+      return 1
+    end
+    vim.treesitter.get_parser = function()
+      return nil
+    end
+    config.setup({
+      ui = {
+        title = {
+          context = {
+            enabled = true,
+          },
+        },
+      },
+    })
+
+    health.check()
+
+    assert.is_true(
+      vim.list_contains(messages, "info:tree-sitter context enabled but no parser for the current buffer filetype")
+    )
+  end)
 end)