This removes much of the AST logic out of main.go,
and makes it easier to build custom vet binaries
The trade-off in this change is for flexibility.
There's very little change in the per-check files,
a lot less code in main.go (specifically the AST walking
logic has shrunk), and it makes it much easier to build
custom vet binaries simply by dropping new source files
in the directory.
LGTM=josharian, r
R=r, josharian, kamil.kisiel
CC=golang-codereviews
https://golang.org/cl/83400043
Over time, a number of modules were added that used Warn instead of Bad
to report problems with the code, but the documentation states that
if there is a problem, the exit code must be 1, not 0. Warn does not set the
exit code and should be used only for internal errors and messages
triggered by the -v flag.
There's nothing substantive here except calling the other function in a few
places.
Fixesgolang/go#7017.
LGTM=crawshaw
R=golang-codereviews, crawshaw
CC=golang-codereviews
https://golang.org/cl/71860044
They will be deleted from their current homes once this has landed.
Changes made to import paths to make the code compile, and to find
errchk in the right place in cmd/vet's Makefile.
TODO in a later CL: tidy up vet.
R=golang-dev, gri
CC=golang-dev
https://golang.org/cl/9495043
