feat: go import handler based on treesitter (#47)

Author: sportshead

.gitmodules

@@ -6,3 +6,7 @@
 	path = test/vendor/plenary.nvim
 	url = https://github.com/nvim-lua/plenary.nvim
   ignore = dirty
+[submodule "test/vendor/nvim-treesitter"]
+	path = test/vendor/nvim-treesitter
+	url = https://github.com/nvim-treesitter/nvim-treesitter
+  ignore = dirty

README.md

@@ -13,6 +13,7 @@
 * open github issues directly in the browser (e.g. `Fixes #22` opens `https://github.com/chrishrb/gx.nvim/issues/22`)
 * dependencies from `package.json` (e.g. line `"express": "^4.18.2",` in the `package.json` opens `https://www.npmjs.com/package/express`)
 * formulae and casks from `Brewfile` (e.g. line `brew "neovim"` in the `Brewfile` opens `https://formulae.brew.sh/formula/neovim`)
+* go packages from an import statement (e.g. line `import "github.com/joho/godotenv"` opens `https://pkg.go.dev/github.com/joho/godotenv`)
 * if there is no url found under the cursor, the word/selection is automatically searched on the web
 * supports user defined handlers to extend the functionality
 * support for macOS, Linux and Windows
@@ -51,6 +52,7 @@ require("lazy").setup({
         brewfile = true, -- open Homebrew formulaes and casks
         package_json = true, -- open dependencies from package.json
         search = true, -- search the web/selection on the web if nothing else is found
+        go = true, -- open pkg.go.dev from an import statement (uses treesitter)
         jira = { -- custom handler to open Jira tickets (these have higher precedence than builtin handlers)
           name = "jira", -- set name of handler
           handle = function(mode, line, _)

lua/gx/handler.lua

@@ -4,6 +4,7 @@ local package_json_handler = require("gx.handlers.package_json")
 local plugin_handler = require("gx.handlers.plugin")
 local url_handler = require("gx.handlers.url")
 local github_handler = require("gx.handlers.github")
+local go_handler = require("gx.handlers.go")
 local commit_handler = require("gx.handlers.commit")
 local markdown_handler = require("gx.handlers.markdown")
 local cve_handler = require("gx.handlers.cve")
@@ -41,6 +42,7 @@ local function resolve_handlers(handlers)
   add_handler(resolved, plugin_handler, handlers.plugin and exists.plugin == nil)
   add_handler(resolved, github_handler, handlers.github and exists.github == nil)
   add_handler(resolved, commit_handler, handlers.commit and exists.commit == nil)
+  add_handler(resolved, go_handler, handlers.go and exists.go == nil)
   add_handler(resolved, markdown_handler, handlers.markdown and exists.markdown == nil)
   add_handler(resolved, cve_handler, handlers.cve and exists.cve == nil)
   add_handler(resolved, url_handler, handlers.url and exists.url == nil)

lua/gx/handlers/go.lua

@@ -0,0 +1,33 @@
+local M = {
+  -- every filetype and filename
+  name = "go",
+  filetype = { "go" },
+  filename = nil,
+}
+
+function M.handle()
+  local node = vim.treesitter.get_node()
+  if not node then
+    return
+  end
+  if node:type() ~= "import_spec" then
+    if node:type() == "import_declaration" then
+      node = node:named_child(0)
+    else
+      node = node:parent()
+    end
+    if node:type() ~= "import_spec" then
+      return
+    end
+  end
+
+  local path_node = node:field("path")[1]
+  local start_line, start_col, end_line, end_col = path_node:range()
+
+  local line = vim.api.nvim_buf_get_lines(0, start_line, end_line + 1, false)[1]
+  local pkg = line:sub(start_col + 2, end_col - 1) -- remove quotes
+
+  return "https://pkg.go.dev/" .. pkg
+end
+
+return M

test/fixtures/test.go

@@ -0,0 +1,10 @@
+package main
+
+import "fmt"
+
+import myio "io"
+
+import (
+	"github.com/joho/godotenv"
+	corev1 "k8s.io/api/core/v1"
+)

test/spec.vim

@@ -1,5 +1,6 @@
 set rtp^=test/vendor/plenary.nvim/
 set rtp^=test/vendor/matcher_combinators.lua/
+set rtp^=test/vendor/nvim-treesitter/
 set rtp^=./
 
 runtime plugin/plenary.vim
@@ -11,3 +12,6 @@ lua require('matcher_combinators.luassert')
 runtime plugin/gx.lua
 " lua require('gx').setup({ name = 'Jane Doe' })
 lua require('gx').setup()
+
+" needed for go handler testing
+lua require('nvim-treesitter.configs').setup({ ensure_installed = { "go" }, sync_install = true })

test/spec/gx/handlers/go_handler_spec.lua

@@ -0,0 +1,23 @@
+local handler = require("gx.handlers.go")
+
+describe("go handler works", function()
+  vim.cmd("edit test/fixtures/test.go")
+  local function test_line(line, startpos, endpos, expected)
+    for i = startpos, endpos do
+      vim.api.nvim_win_set_cursor(0, { line, i })
+      assert.equals(expected, handler.handle())
+    end
+  end
+  it("parses single line imports", function()
+    test_line(3, 0, 11, "https://pkg.go.dev/fmt")
+  end)
+  it("parses single line named imports", function()
+    test_line(5, 0, 15, "https://pkg.go.dev/io")
+  end)
+  it("parses imports in list", function()
+    test_line(8, 1, 26, "https://pkg.go.dev/github.com/joho/godotenv")
+  end)
+  it("parses named imports in list", function()
+    test_line(9, 1, 27, "https://pkg.go.dev/k8s.io/api/core/v1")
+  end)
+end)