internal/lsp/source: derive document symbols from syntax alone

The documentSymbols handler joined syntax information with type
information, meaning that it was only able to satisfy requests for files
in valid workspace packages. However, the value added by type
information was limited, and in many cases could be derived from syntax
alone. For example, while generating symbols for a const declaration, we
don't need the type checker to tell us that the symbol kind is const.

Refactor the documentSymbols handler to derive symbols from syntax
alone. This leads to some simplifications from the code, in addition to
eliminating the dependency on package data. Also, simplify symbol
details to just use types.ExprString, which includes some missing
information such as function return values. Also, update handling to
support Go 1.18 type embedding in interfaces.

Notably, this reverts decisions like golang/go#31202, in which we went to
effort to make the symbol kind more accurate. In my opinion (and the
opinion expressed in golang/go#52797), the cost of requiring type
information is not worth the minor improvement in accuracy of the symbol
kind, which (as far as I know) is only used for UI elements.

To facilitate testing (and start to clean up the test framework), make
several simplifications / improvements to the marker tests:
- simplify the collection of symbol data
- eliminate unused marks
- just use cmp.Diff for comparing results
- allow for arbitrary nesting of symbols.
- remove unnecessary @symbol annotations from workspace_symbol tests --
  their data is not used by workspace_symbol handlers
- remove Symbol and WorkspaceSymbol handlers from source_test.go. On
  inspection, these handlers were redundant with lsp_test.go.
Notably, the collection and assembly of @symbol annotations is still way
too complicated. It would be much simpler to just have a single golden
file summarizing the entire output, rather than weaving it together from
annotations. However, I realized this too late, and so it will have to
wait for a separate CL.

Fixes golang/go#52797
Fixes golang/vscode-go#2242
Updates golang/go#54845

Change-Id: I3a2c2d39f59f9d045a6cedf8023ff0c80a69d974
gopls-CI: kokoro <>
TryBot-Result: Gopher Robot <>
Reviewed-by: Hyang-Ah Hana Kim <>
Run-TryBot: Robert Findley <>
Reviewed-by: Alan Donovan <>
24 files changed
tree: 60cf20b7d8ee189eef53317c2dc3f89992ddc1a0
  1. benchmark/
  2. blog/
  3. cmd/
  4. container/
  5. copyright/
  6. cover/
  7. go/
  8. godoc/
  9. gopls/
  10. imports/
  11. internal/
  12. playground/
  13. present/
  14. refactor/
  15. txtar/
  16. .gitattributes
  17. .gitignore
  18. .prettierrc
  19. codereview.cfg
  21. go.mod
  22. go.sum

Go Tools


This repository provides the module, comprising various tools and packages mostly for static analysis of Go programs, some of which are listed below. Use the “Go reference” link above for more information about any package.

It also contains the module, whose root package is a language-server protocol (LSP) server for Go. An LSP server analyses the source code of a project and responds to requests from a wide range of editors such as VSCode and Vim, allowing them to support IDE-like functionality.

Selected commands:

  • cmd/goimports formats a Go program like go fmt and additionally inserts import statements for any packages required by the file after it is edited.
  • cmd/callgraph prints the call graph of a Go program.
  • cmd/digraph is a utility for manipulating directed graphs in textual notation.
  • cmd/stringer generates declarations (including a String method) for “enum” types.
  • cmd/toolstash is a utility to simplify working with multiple versions of the Go toolchain.

These commands may be fetched with a command such as go install

Selected packages:

  • go/ssa provides a static single-assignment form (SSA) intermediate representation (IR) for Go programs, similar to a typical compiler, for use by analysis tools.

  • go/packages provides a simple interface for loading, parsing, and type checking a complete Go program from source code.

  • go/analysis provides a framework for modular static analysis of Go programs.

  • go/callgraph provides call graphs of Go programs using a variety of algorithms with different trade-offs.

  • go/ast/inspector provides an optimized means of traversing a Go parse tree for use in analysis tools.

  • go/cfg provides a simple control-flow graph (CFG) for a Go function.

  • go/expect reads Go source files used as test inputs and interprets special comments within them as queries or assertions for testing.

  • go/gcexportdata and go/gccgoexportdata read and write the binary files containing type information used by the standard and gccgo compilers.

  • go/types/objectpath provides a stable naming scheme for named entities (“objects”) in the go/types API.

Numerous other packages provide more esoteric functionality.


This repository uses Gerrit for code changes. To learn how to submit changes, see

The main issue tracker for the tools repository is located at Prefix your issue with “x/tools/(your subdir):” in the subject line, so it is easy to find.

JavaScript and CSS Formatting

This repository uses prettier to format JS and CSS files.

The version of prettier used is 1.18.2.

It is encouraged that all JS and CSS code be run through this before submitting a change. However, it is not a strict requirement enforced by CI.