merge upstream

.github/ISSUE_TEMPLATE/01-crash.md

@@ -0,0 +1,18 @@
+---
+name: Crash
+about: Using tsgo or the language server caused a panic
+title: ''
+labels: Crash
+assignees: ''
+
+---
+
+## Stack trace
+
+```
+[paste stack trace here]
+```
+
+## Steps to reproduce
+
+1.

.github/ISSUE_TEMPLATE/02-behavior-difference.md

@@ -0,0 +1,16 @@
+---
+name: Behavior Difference
+about: tsgo produces different results than TypeScript 5.8
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+## Steps to reproduce
+
+<!-- Share a repository link or a code sample -->
+
+## Behavior with `[email protected]`
+
+## Behavior with `tsgo`

.github/ISSUE_TEMPLATE/03-other.md

@@ -0,0 +1,10 @@
+---
+name: Other
+about: Something else
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+

.github/ISSUE_TEMPLATE/04-copilot-pr-porting.md

@@ -0,0 +1,26 @@
+---
+name: '[TypeScript Team Use] Copilot PR porting'
+about: Instructions for Copilot to port a PR from microsoft/TypeScript
+title: 'Port TypeScript PR #[NNNNN]'
+labels: Porting PR
+assignees: ''
+
+---
+
+This repository is a port of microsoft/TypeScript from TypeScript to Go. Since the port began, the following pull request was applied to microsoft/TypeScript. An equivalent change now needs to be applied here.
+
+## PR to port
+
+- PR link: <!-- https://github.com/microsoft/TypeScript/pull/NNNNN -->
+- Squash commit diff: <!-- Copy the squash commit link and append ".patch", e.g. https://github.com/microsoft/TypeScript/commit/a271797c1a95494e5f7aa8075c01941ad25cad08.patch -->
+
+## Instructions
+
+1. Use `playwright` to view the PR listed above
+2. Apply the edits made in that PR to this codebase, translating them from TypeScript to Go.
+   - The change may or may not be applicable. It may have already been ported. Do not make any significant changes outside the scope of the diff. If the change cannot be applied without significant out-of-scope changes, explain why and stop working.
+   - Tip: search for functions and identifiers from the diff to find the right location to apply edits. Some files in microsoft/TypeScript have been split into multiple.
+   - Tip: some changes have already been ported, like changes to diagnostic message text. Tests do not need to be ported as they are imported from the submodule.
+3. Refer to your copilot_instructions.md for guidance on how to build and test your change. Note the following differences to the typical development workflow:
+   - Since you are porting the implementation for a behavior that already has tests in the submodule, you don't need to add new tests. Instead, your change should change existing baselines.
+   - If done correctly, you should see removals in `.diff` baselines. These `.diff` removals are your ultimate source of truth: your change is not correct unless diffs are reduced.

.github/actions/setup-go/action.yml

@@ -19,15 +19,16 @@ runs:
         go-version: ${{ inputs.go-version }}
         cache: false
 
+    # There is more code downloaded and built than is covered by '**/go.sum',
+    # so give each job its own cache to try and not end up sharing the wrong
+    # cache between jobs, and hash the Herebyfile and golancgi-lint version.
+
     - name: Go cache
       uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
       with:
-        # There is more code downloaded and built than is covered by '**/go.sum',
-        # so give each job its own cache to try and not end up sharing the wrong
-        # cache between jobs.
         key: ts-setup-go-${{ runner.os }}-${{ steps.install-go.outputs.go-version }}-${{ hashFiles('**/go.sum', '**/Herebyfile.mjs', '**/.custom-gcl.yml') }}-${{ github.workflow }}-${{ inputs.cache-name }}
         restore-keys: |
-          ts-setup-go-${{ runner.os }}-${{ steps.install-go.outputs.go-version }}-${{ hashFiles('**/go.sum', '**/Herebyfile.mjs', '**/.custom-gcl.yml') }}
+          ts-setup-go-${{ runner.os }}-${{ steps.install-go.outputs.go-version }}-${{ hashFiles('**/go.sum', '**/Herebyfile.mjs', '**/.custom-gcl.yml') }}-${{ github.workflow }}-
         path: |
           ~/go/pkg/mod
           ~/.cache/go-build

.github/codeql/codeql-configuration.yml

@@ -9,3 +9,6 @@ query-filters:
   # This query takes too long on complicated string manipulations
   - exclude:
       id: go/unsafe-quoting
+  # Times out in our code.
+  - exclude:
+      id: go/allocation-size-overflow

.github/copilot-instructions.md

@@ -9,23 +9,29 @@ Most of our development takes place in the `internal` directory, and most behavi
 
 Most development on the codebase is in Go.
 Standard Go commands and practices apply, but we primarily use a tool called `hereby` to build, run tests, and other tasks.
-Feel free to install `hereby` globally (`npm install -g hereby`) if it is easier, and run `hereby --list` to see all available commands.
+Run `npx hereby --list` to see all available commands.
 
 ```sh
-hereby build  # Build the project
-hereby test   # Run tests
-hereby format # Format the code
-hereby lint   # Run linters
+npx hereby build  # Build the project
+npx hereby test   # Run tests
+npx hereby format # Format the code
+npx hereby lint   # Run linters
+
+# To run a specific compiler test:
+go test -run='TestSubmodule/<test name>' ./internal/testrunner  # For submodule tests in _submodules/TypeScript
+go test -run='TestLocal/<test name>' ./internal/testrunner     # For local tests in testdata/tests/cases
 ```
 
-Always make sure code is formatted, linted, and tested before sending a pull request.
-
+Always make sure code is formatted, linted, and tested before sending a pull request.
+
 ## Compiler Features, Fixes, and Tests
 
 When fixing a bug or implementing a new feature, at least one minimal test case should always be added in advance to verify the fix.
 This project primarily uses snapshot/baseline/golden tests rather than unit tests.
 New compiler tests are written in `.ts`/`.tsx` files in the directory `testdata/tests/cases/compiler/`, and are written in the following format:
 
+**Note:** Issues with editor features cannot be tested with compiler tests in `testdata/tests/cases/`. Editor functionality requires integration testing with the language server.
+
 ```ts
 // @target: esnext
 // @module: preserve
@@ -79,6 +85,12 @@ It is ideal to implement features and fixes in the following order, and commit c
 
 It is fine to implement more and more of a feature across commits, but be sure to update baselines every time so that reviewers can measure progress.
 
+## Code Porting Reference
+
+The code in `internal` is ported from the code in `_submodules/TypeScript`.
+When implementing features or fixing bugs, those files should be searched for similar functions when code is either missing or potentially wrong.
+The TypeScript submodule serves as the reference implementation for behavior and functionality.
+
 # Other Instructions
 
 - Do not add or change existing dependencies unless asked to.

.github/workflows/ci.yml

@@ -250,11 +250,8 @@ jobs:
       - run: node ./internal/lsp/lsproto/_generate/fetchModel.mjs
       - run: node ./internal/lsp/lsproto/_generate/generate.mjs
 
-      - name: Remove all converted fourslash tests
-        run: rm -rf internal/fourslash/tests/gen
-
-      - name: Regenerate fourslash tests
-        run: npm run convertfourslash
+      - name: Regenerate fourslash tests and update failing test list
+        run: npm run updatefailing
 
       - run: git add .
       - run: git diff --staged --exit-code --stat

.github/workflows/codeql.yml

@@ -48,7 +48,7 @@ jobs:
 
       # Initializes the CodeQL tools for scanning.
       - name: Initialize CodeQL
-        uses: github/codeql-action/init@ce28f5bb42b7a9f2c824e633a3f6ee835bab6858 # v3.29.0
+        uses: github/codeql-action/init@39edc492dbe16b1465b0cafca41432d857bdb31a # v3.29.1
         with:
           config-file: ./.github/codeql/codeql-configuration.yml
         # Override language selection by uncommenting this and choosing your languages
@@ -58,7 +58,7 @@ jobs:
       # Autobuild attempts to build any compiled languages (C/C++, C#, or Java).
       # If this step fails, then you should remove it and run the build manually (see below).
       - name: Autobuild
-        uses: github/codeql-action/autobuild@ce28f5bb42b7a9f2c824e633a3f6ee835bab6858 # v3.29.0
+        uses: github/codeql-action/autobuild@39edc492dbe16b1465b0cafca41432d857bdb31a # v3.29.1
 
       # ℹ️ Command-line programs to run using the OS shell.
       # 📚 See https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#jobsjob_idstepsrun
@@ -72,4 +72,4 @@ jobs:
       #     make release
 
       - name: Perform CodeQL Analysis
-        uses: github/codeql-action/analyze@ce28f5bb42b7a9f2c824e633a3f6ee835bab6858 # v3.29.0
+        uses: github/codeql-action/analyze@39edc492dbe16b1465b0cafca41432d857bdb31a # v3.29.1

.github/workflows/copilot-setup-steps.yml

@@ -23,8 +23,13 @@ jobs:
       - uses: dtolnay/rust-toolchain@fcf085fcb4b4b8f63f96906cd713eb52181b5ea4 # stable
       - uses: ./.github/actions/setup-go
         with:
+          # Updated to 1.25.0-rc.1 to improve compilation time
+          go-version: '>=1.25.0-rc.1'
           cache-name: copilot-setup-steps
       - run: npm i -g @playwright/[email protected]
       - run: npm ci
       # pull dprint caches before network access is blocked
       - run: npx hereby check:format || true
+      # cache build and lint operations
+      - run: npx hereby build || true
+      - run: npx hereby lint || true

.golangci.yml

@@ -63,6 +63,10 @@ linters:
         type: module
 
   exclusions:
+    rules:
+      - path: internal/fourslash/tests/gen/
+        linters: misspell
+
     presets:
       - comments
       - std-error-handling

cmd/tsgo/api.go

@@ -26,7 +26,6 @@ func runAPI(args []string) int {
 		Out:                os.Stdout,
 		Err:                os.Stderr,
 		Cwd:                *cwd,
-		NewLine:            "\n",
 		DefaultLibraryPath: defaultLibraryPath,
 	})
 

cmd/tsgo/sys.go

@@ -4,11 +4,9 @@ import (
 	"fmt"
 	"io"
 	"os"
-	"runtime"
 	"time"
 
 	"github.com/microsoft/typescript-go/internal/bundled"
-	"github.com/microsoft/typescript-go/internal/core"
 	"github.com/microsoft/typescript-go/internal/execute"
 	"github.com/microsoft/typescript-go/internal/tspath"
 	"github.com/microsoft/typescript-go/internal/vfs"
@@ -19,7 +17,6 @@ type osSys struct {
 	writer             io.Writer
 	fs                 vfs.FS
 	defaultLibraryPath string
-	newLine            string
 	cwd                string
 	start              time.Time
 }
@@ -44,10 +41,6 @@ func (s *osSys) GetCurrentDirectory() string {
 	return s.cwd
 }
 
-func (s *osSys) NewLine() string {
-	return s.newLine
-}
-
 func (s *osSys) Writer() io.Writer {
 	return s.writer
 }
@@ -69,7 +62,6 @@ func newSystem() *osSys {
 		fs:                 bundled.WrapFS(osvfs.FS()),
 		defaultLibraryPath: bundled.LibPath(),
 		writer:             os.Stdout,
-		newLine:            core.IfElse(runtime.GOOS == "windows", "\r\n", "\n"),
 		start:              time.Now(),
 	}
 }

internal/api/api.go

@@ -111,11 +111,6 @@ func (api *API) Trace(s string) {
 	api.options.Logger.Info(s)
 }
 
-// NewLine implements ProjectHost.
-func (api *API) NewLine() string {
-	return api.host.NewLine()
-}
-
 // PositionEncoding implements ProjectHost.
 func (api *API) PositionEncoding() lsproto.PositionEncodingKind {
 	return lsproto.PositionEncodingKindUTF8

internal/api/host.go

@@ -6,5 +6,4 @@ type APIHost interface {
 	FS() vfs.FS
 	DefaultLibraryPath() string
 	GetCurrentDirectory() string
-	NewLine() string
 }

internal/api/server.go

@@ -61,7 +61,6 @@ type ServerOptions struct {
 	Out                io.Writer
 	Err                io.Writer
 	Cwd                string
-	NewLine            string
 	DefaultLibraryPath string
 }
 
@@ -98,7 +97,6 @@ func NewServer(options *ServerOptions) *Server {
 		w:                  bufio.NewWriter(options.Out),
 		stderr:             options.Err,
 		cwd:                options.Cwd,
-		newLine:            options.NewLine,
 		fs:                 bundled.WrapFS(osvfs.FS()),
 		defaultLibraryPath: options.DefaultLibraryPath,
 	}
@@ -126,11 +124,6 @@ func (s *Server) GetCurrentDirectory() string {
 	return s.cwd
 }
 
-// NewLine implements APIHost.
-func (s *Server) NewLine() string {
-	return s.newLine
-}
-
 func (s *Server) Run() error {
 	for {
 		messageType, method, payload, err := s.readRequest("")