go/types/objectpath: add support for type parameters

This CL adds an initial draft of support for type parameters in the
go/types/objectpath package. For now, introduce two new operators:
 - the 'T' operator (type->type), which requires an integer operand and
   goes from *Named and *Signature types to the type parameter at the
   given index.
 - the 'C' operator (type->type), which goes from a *TypeParam type to
   its constraint.

Along the way, reorganize the path tests and update some errors messages
to consistently format the expected type with %T.

Fixes golang/go#48588

Change-Id: Ibdf03a86b7d8e24a8faa1f2fc42f2be8db20ca75
Reviewed-on: https://go-review.googlesource.com/c/tools/+/350148
Trust: Robert Findley <rfindley@google.com>
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
gopls-CI: kokoro <noreply+kokoro@google.com>
Reviewed-by: Tim King <taking@google.com>
3 files changed
tree: b3884f8f543021f29958b421c683081ddb5976f3
  1. .gitattributes
  2. .gitignore
  3. .prettierrc
  4. AUTHORS
  5. CONTRIBUTING.md
  6. CONTRIBUTORS
  7. LICENSE
  8. PATENTS
  9. README.md
  10. benchmark/
  11. blog/
  12. cmd/
  13. codereview.cfg
  14. container/
  15. copyright/
  16. cover/
  17. go.mod
  18. go.sum
  19. go/
  20. godoc/
  21. gopls/
  22. imports/
  23. internal/
  24. playground/
  25. present/
  26. refactor/
  27. txtar/
README.md

Go Tools

PkgGoDev

This subrepository holds the source for various packages and tools that support the Go programming language.

Some of the tools, godoc and vet for example, are included in binary Go distributions.

Others, including the Go guru and the test coverage tool, can be fetched with go get.

Packages include a type-checker for Go and an implementation of the Static Single Assignment form (SSA) representation for Go programs.

Download/Install

The easiest way to install is to run go get -u golang.org/x/tools/.... You can also manually git clone the repository to $GOPATH/src/golang.org/x/tools.

JS/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.

Report Issues / Send Patches

This repository uses Gerrit for code changes. To learn how to submit changes to this repository, see https://golang.org/doc/contribute.html.

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