feat(lsp)!: Replaced one-off LSP command with persistent LSP server (#1131)

fix(compiler): Avoid module aliases of themselves
chore(compiler): Add char_at utility
chore(compiler): Remove an extra Option binding in filepath resolution
chore(compiler): Introduce grain_formatting library
chore(compiler): Introduce language_server library
chore(compiler)!: Remove `--lsp` flag from grainc executable
chore(compiler): Add `grainlsp` executable

Co-authored-by: Marcus Roberts <marcus@marcusr.com>
Co-authored-by: Blaine Bublitz <blaine.bublitz@gmail.com>
Co-authored-by: Oscar Spencer <oscar@grain-lang.org>

Author: 4 people

.gitignore

@@ -41,5 +41,7 @@ cli/bin/graindoc.exe
 cli/bin/graindoc.bc.js
 cli/bin/grainformat.exe
 cli/bin/grainformat.bc.js
+cli/bin/grainlsp.exe
+cli/bin/grainlsp.bc.js
 
 .DS_Store

cli/.prettierignore

@@ -1,4 +1,5 @@
 bin/grainc.bc.js
 bin/graindoc.bc.js
 bin/grainformat.bc.js
+bin/grainlsp.bc.js
 CHANGELOG.md

cli/bin/exec.js

@@ -93,8 +93,30 @@ function execGrainformat(
   );
 }
 
+function getGrainlsp() {
+  const grainlsp = path.join(__dirname, "grainlsp.exe");
+
+  // TODO: Maybe make an installable path & check it?
+  if (process.pkg || !fs.existsSync(grainlsp)) {
+    const node = process.execPath;
+    const grainlsp_js = path.join(__dirname, "grainlsp.js");
+    return `"${node}" ${grainlsp_js}`;
+  }
+
+  return `${grainlsp}`;
+}
+
+const grainlsp = getGrainlsp();
+
+function execGrainlsp(options, program, execOpts = { stdio: "inherit" }) {
+  const flags = flagsFromOptions(program, options);
+
+  return execSync(`${grainlsp} ${flags.join(" ")}`, execOpts);
+}
+
 module.exports = {
   grainc: execGrainc,
   graindoc: execGraindoc,
   grainformat: execGrainformat,
+  grainlsp: execGrainlsp,
 };

cli/bin/grain.js

@@ -218,18 +218,9 @@ program
   .action(run);
 
 program
-  .command("lsp <file>")
-  .description("check a grain file for LSP")
-  .action(function (file, options, program) {
-    // The lsp subcommand inherits all options of the
-    // top level grain command
-
-    // call the compiler, passing stdio through so the compiler gets the source code on stdin
-    // and we get the compiler output in stdout
-    // we still take the file name so we have it available
-
-    exec.grainc(`--lsp ${file}`, options, program);
-  });
+  .command("lsp")
+  .description("start the Grain LSP server")
+  .action(exec.grainlsp);
 
 program
   .command("doc <file|dir>")

cli/bin/grainlsp.js

@@ -0,0 +1,3 @@
+// A wrapper around grainlsp.bc.js that prepares the `pkg` env
+require("./pkg");
+require("./grainlsp.bc.js");

compiler/dune

@@ -1,9 +1,9 @@
 (alias
  (name native)
  (deps grainc/grainc.exe graindoc/graindoc.exe grainformat/grainformat.exe
-   test/test.exe))
+   grainlsp/grainlsp.exe test/test.exe))
 
 (alias
  (name js)
  (deps grainc/grainc.bc.js graindoc/graindoc.bc.js
-   grainformat/grainformat.bc.js test/test.bc.js))
+   grainformat/grainformat.bc.js grainlsp/grainlsp.bc.js test/test.bc.js))

compiler/dune-project

@@ -30,6 +30,18 @@
   (name grainformat)
   (synopsis "Grain formatter"))
 
+(package
+  (name grainlsp)
+  (synopsis "Grain LSP"))
+
+(package
+  (name grain_language_server)
+  (synopsis "Grain Language Server Protocol"))
+
+(package
+ (name grain_formatting)
+ (synopsis "Grain formatting"))
+
 (package
   (name grain_linking)
   (synopsis "The Grain linker"))

compiler/esy.json

@@ -2,9 +2,7 @@
   "name": "@grain/compiler",
   "version": "0.4.6",
   "esy": {
-    "build": [
-      "dune build @native --no-buffer"
-    ],
+    "build": ["dune build @native --no-buffer"],
     "buildEnv": {
       "DUNE_BUILD_DIR": "#{self.target_dir}",
       "GRAIN_STDLIB": "#{self.root / '..' / 'stdlib'}",
@@ -14,14 +12,16 @@
       "GRAINDOC_JS_PATH": "#{self.target_dir / 'default' / 'graindoc' / 'graindoc.bc.js'}",
       "GRAINFORMAT_BIN_PATH": "#{self.target_dir / 'default' / 'grainformat' / 'grainformat.exe'}",
       "GRAINFORMAT_JS_PATH": "#{self.target_dir / 'default' / 'grainformat' / 'grainformat.bc.js'}",
+      "GRAINLSP_BIN_PATH": "#{self.target_dir / 'default' / 'grainlsp' / 'grainlsp.exe'}",
+      "GRAINLSP_JS_PATH": "#{self.target_dir / 'default' / 'grainlsp' / 'grainlsp.bc.js'}",
       "CLI_BIN_DIR": "#{self.root / '..' / 'cli' / 'bin'}",
       "TEST_EXEC_PATH": "#{self.target_dir / 'default' / 'test' / 'test.exe'}",
       "TEST_JS_PATH": "#{self.target_dir / 'default' / 'test' / 'test.bc.js'}"
     }
   },
   "scripts": {
-    "copy:exe": "cp #{$GRAINC_BIN_PATH} #{$GRAINDOC_BIN_PATH} #{$GRAINFORMAT_BIN_PATH} #{$CLI_BIN_DIR}",
-    "copy:js": "cp #{$GRAINC_JS_PATH} #{$GRAINDOC_JS_PATH} #{$GRAINFORMAT_JS_PATH} #{$CLI_BIN_DIR}",
+    "copy:exe": "cp #{$GRAINC_BIN_PATH} #{$GRAINDOC_BIN_PATH} #{$GRAINFORMAT_BIN_PATH} #{$GRAINLSP_BIN_PATH} #{$CLI_BIN_DIR}",
+    "copy:js": "cp #{$GRAINC_JS_PATH} #{$GRAINDOC_JS_PATH} #{$GRAINFORMAT_JS_PATH} #{$GRAINLSP_JS_PATH}  #{$CLI_BIN_DIR}",
     "clean": "rm -rf #{self.root}/_esy",
     "test": "#{$TEST_EXEC_PATH}",
     "test:js": "node #{$TEST_JS_PATH}",
@@ -38,11 +38,13 @@
     "@opam/fs": "0.0.2",
     "@opam/menhir": "20211125",
     "@opam/ocamlgraph": ">= 2.0.0",
+    "@opam/ppx_deriving": ">= 5.2.1",
     "@opam/ppx_deriving_cmdliner": ">= 0.6.0",
     "@opam/ppx_deriving_yojson": ">= 3.5.2",
     "@opam/ppx_sexp_conv": ">= 0.14.0",
     "@opam/reason": ">= 3.6.2",
     "@opam/sexplib": ">= 0.14.0",
+    "@opam/uri": ">= 4.2.0 < 5.0.0",
     "@opam/utf8": "0.1.0",
     "@opam/yojson": ">= 1.7.0",
     "ocaml": "4.12.0"