CL 711640 removed unneeded loop variables in tests; since 1.22 they are no more needed.
Some leftover are present after that CL, and were addressed partly by CL 719600 and CL 711801.
# git ls-files | xargs -I {} perl -nE 'print "$ARGV:$.:$_" if /\s+(\w+) := \1$/' {} | grep _test
src/cmd/api/api_test.go:235: context := context
src/cmd/cgo/internal/testerrors/errors_test.go:155: cflags := cflags
src/cmd/cgo/internal/testsanitizers/asan_test.go:51: tc := tc
src/cmd/cgo/internal/testsanitizers/cshared_test.go:57: tc := tc
src/cmd/cgo/internal/testsanitizers/libfuzzer_test.go:46: tc := tc
src/cmd/cgo/internal/testsanitizers/msan_test.go:65: tc := tc
src/cmd/cgo/internal/testsanitizers/tsan_test.go:62: tc := tc
src/cmd/cgo/internal/teststdio/stdio_test.go:59: file := file
src/cmd/compile/internal/test/reproduciblebuilds_test.go:29: test := test
src/cmd/compile/internal/test/ssa_test.go:166: test := test
src/cmd/compile/internal/types2/api_test.go:2423: i := i
src/cmd/compile/internal/types2/api_test.go:2602: test := test
src/cmd/compile/internal/types2/sizes_test.go:187: tc := tc
src/cmd/compile/internal/types2/stdlib_test.go:62: dir := dir
src/cmd/go/go_test.go:1548: tt := tt
src/cmd/go/internal/modfetch/coderepo_test.go:822: tt := tt
src/cmd/go/internal/modfetch/coderepo_test.go:905: tt := tt
src/cmd/go/internal/modload/query_test.go:182: tt := tt
src/cmd/go/internal/web/url_test.go:17: tc := tc
src/cmd/go/internal/web/url_test.go:49: tc := tc
src/cmd/go/script_test.go:110: file := file
src/cmd/internal/par/queue_test.go:54: i := i
src/cmd/link/dwarf_test.go:85: prog := prog
src/cmd/link/dwarf_test.go:86: expectDWARF := expectDWARF
src/cmd/link/internal/ld/deadcode_test.go:37: test := test
src/cmd/link/internal/ld/dwarf_test.go:411: tc := tc
src/cmd/link/internal/ld/dwarf_test.go:476: tc := tc
src/cmd/link/internal/ld/dwarf_test.go:558: tc := tc
src/cmd/link/internal/ld/dwarf_test.go:1983: opt := opt
src/cmd/link/internal/ld/ld_test.go:357: tt := tt
src/cmd/link/link_test.go:1625: test := test
src/crypto/md5/md5_test.go:290: buf := buf
src/math/big/arith_test.go:62: name := name
src/math/big/arith_test.go:68: zz := zz
src/math/big/arith_test.go:115: name := name
src/math/big/arith_test.go:121: zz1 := zz1
src/math/big/arith_test.go:122: zz2 := zz2
src/math/big/arith_test.go:178: name := name
src/math/big/arith_test.go:183: zz := zz
src/math/big/arith_test.go:244: name := name
src/math/big/arith_test.go:249: zz := zz
src/math/big/arith_test.go:295: name := name
src/math/big/arith_test.go:301: zz := zz
src/math/big/arith_test.go:349: name := name
src/math/big/arith_test.go:355: zz := zz
src/os/os_windows_test.go:1237: tt := tt
src/runtime/panic_test.go:42: t := t
src/runtime/syscall_windows_test.go:781: arglen := arglen
src/unicode/letter_test.go:470: tab := tab
src/unicode/letter_test.go:479: tab := tabAll copies could be removed, but the ones in math and unicode.
CL 711640 removed unneeded loop variables in tests; since 1.22 they are no more needed.
Some leftover are present after that CL, and were addressed partly by CL 719600 and CL 711801.
All copies could be removed, but the ones in
mathandunicode.