internal/lsp/cache: avoid string(int) conversion

LoadMode and ParseMode are currently hashed with a string(int)
conversion, but this conversion is now discouraged (see the vet check
'stringintconv' for more information). Since the hash uses the code
point, this change replaces these instances with string(rune(int)).

Updates golang/go#32479.

Change-Id: I0d8e91d073fc34ac9faafe75a0d86cf71a5327d4
Reviewed-on: https://go-review.googlesource.com/c/tools/+/232679
Reviewed-by: Rebecca Stambler <[email protected]>
Run-TryBot: Rebecca Stambler <[email protected]>
TryBot-Result: Gobot Gobot <[email protected]>

Author: smasher164

internal/lsp/cache/check.go

@@ -170,7 +170,7 @@ func hashConfig(config *packages.Config) string {
 
 	// Dir, Mode, Env, BuildFlags are the parts of the config that can change.
 	b.WriteString(config.Dir)
-	b.WriteString(string(config.Mode))
+	b.WriteString(string(rune(config.Mode)))
 
 	for _, e := range config.Env {
 		b.WriteString(e)

internal/lsp/cache/parse.go

@@ -111,7 +111,7 @@ func (pgh *parseGoHandle) Cached() (*ast.File, []byte, *protocol.ColumnMapper, e
 func hashParseKey(ph source.ParseGoHandle) string {
 	b := bytes.NewBuffer(nil)
 	b.WriteString(ph.File().Identity().String())
-	b.WriteString(string(ph.Mode()))
+	b.WriteString(string(rune(ph.Mode())))
 	return hashContents(b.Bytes())
 }