This is close to what the compiler used to say, except now we say
"as T value" rather than "as type T" which is closer to the truth
(we cannot use a value as a type, after all). Also, place the primary
error and the explanation (cause) on a single line.
Make respective (single line) adjustment to the matching "cannot
convert" error.
Adjust various tests.
For #55326.
Change-Id: Ib646cf906b11f4129b7ed0c38cf16471f9266b88
Reviewed-on: https://go-review.googlesource.com/c/go/+/436176
Reviewed-by: Robert Griesemer <gri@google.com>
Run-TryBot: Robert Griesemer <gri@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>
Reviewed-by: Robert Findley <rfindley@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Compromise between old compiler error "T.m redeclared in this block"
(where the "in this block" is not particularly helpful) and the old
type-checker error "method m already declared for type T ...".
In the case where we have position information for the original
declaration, the error message is "method T.m already declared at
<position>". The new message is both shorter and more precise.
For #55326.
Change-Id: Id4a7f326fe631b11db9e8030eccb417c72d6c7db
Reviewed-on: https://go-review.googlesource.com/c/go/+/435016
Run-TryBot: Robert Griesemer <gri@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@google.com>
Reviewed-by: Robert Findley <rfindley@google.com>
When being used by the compiler, fix up types2 error messages to be more
like Go 1.17 compiler errors. In particular:
- add information about which method is missing when a type is not
assignable/convertible/etc. to an interface.
- add information about any existing method which has the same name,
but wrong type.
- add extra hint in the case that the source or destination type is a
pointer to an interface, rather than an interface.
- add extra hint "need type assertion" in the case that the source is
an interface that is implemented by the destination.
- the following change in the CL stack also adds information about any
existing method with a different name that only differs in case.
Include much of the new logic in a new common function
(*Checker).missingMethodReason().
types2 still adds a little more information in some cases then the Go
1.17 compiler. For example, it typically says "(value of type T)",
rather than "(type T)", where "value" could also be "constant",
"variable", etc.
I kept the types2 error messages almost all the same when types2 is not
used by the compiler. The only change (to reduce amount of compatibility
code) was to change "M method" phrasing in one case to "method M"
phrasing in one error message (which is the phrasing it uses in all
other cases). That is the reason that there are a few small changes in
types2/testdata/check/*.src.
Added new test test/fixedbugs/issue48471.go to test that the added
information is appearing correctly.
Also adjusted the pattern matching in a bunch of other
test/fixedbugs/*.go, now that types2 is producing error messages closer
to Go 1.17. Was able to remove a couple test files from the types2
exception list in run.go.
Updated #48471
Change-Id: I8af1eae6eb8a5541d8ea20b66f494e2e795e1956
Reviewed-on: https://go-review.googlesource.com/c/go/+/363436
Trust: Dan Scales <danscales@google.com>
Run-TryBot: Dan Scales <danscales@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Added a new flag -G to run. Setting -G (as in: go run run.go -G)
will run tests marked with "errorcheck" (and no other flags) also
with the compiler using the new typechecker.
Many tests don't pass yet (due to discrepancies in error messages).
The top-level tests in the test directory which don't pass yet have
been explicitly excluded, permitting to see the current status.
Future CLs will bring error messages in sync and eventually all
tests should pass.
Change-Id: I7caf5eff413e173f68d092af4bbe458434718d74
Reviewed-on: https://go-review.googlesource.com/c/go/+/274313
Trust: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
This CL changes "T literal.M" error message to "T{...}.M". It's clearer
expression and focusing user on actual issue.
Updates #38745
Change-Id: I84b455a86742f37e0bde5bf390aa02984eecc3c9
Reviewed-on: https://go-review.googlesource.com/c/go/+/253677
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
There were multiple ad hoc ways to create method symbols, with subtle
and confusing differences between them. This CL unifies them into a
single well-documented encoding and implementation.
This introduces some inconsequential changes to symbol format for the
sake of simplicity and consistency. Two notable changes:
1) Symbol construction is now insensitive to the package currently
being compiled. Previously, non-exported methods on anonymous types
received different method symbols depending on whether the method was
local or imported.
2) Symbols for method values parenthesized non-pointer receiver types
and non-exported method names, and also always package-qualified
non-exported method names. Now they use the same rules as normal
method symbols.
The methodSym function is also now stricter about rejecting
non-sensical method/receiver combinations. Notably, this means that
typecheckfunc needs to call addmethod to validate the method before
calling declare, which also means we no longer emit errors about
redeclaring bogus methods.
Change-Id: I9501c7a53dd70ef60e5c74603974e5ecc06e2003
Reviewed-on: https://go-review.googlesource.com/104876
Reviewed-by: Robert Griesemer <gri@golang.org>
Plus a few minor changes.
For #18130.
Change-Id: Ica6503fe9c888cc05c15b46178423f620c087491
Reviewed-on: https://go-review.googlesource.com/35233
Reviewed-by: Alan Donovan <adonovan@google.com>
Known issues:
- needs many more tests
- duplicate method declarations via type alias names are not detected
- type alias cycle error messages need to be improved
- need to review setup of byte/rune type aliases
For #18130.
Change-Id: Icc2fefad6214e5e56539a9dcb3fe537bf58029f8
Reviewed-on: https://go-review.googlesource.com/35121
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reason: Decision to back out current alias implementation.
Leaving import/export related code in place for now.
For #16339.
TBR=mdempsky
Change-Id: Ib0897cab2c1c3dc8a541f2efb9893271b0b0efe2
Reviewed-on: https://go-review.googlesource.com/32757
Reviewed-by: Robert Griesemer <gri@golang.org>
This CL completes support for alias declarations in the compiler.
Also:
- increased export format version
- updated various comments
For #16339.
Fixes#17487.
Change-Id: Ic6945fc44c0041771eaf9dcfe973f601d14de069
Reviewed-on: https://go-review.googlesource.com/32090
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>