bazel: migrate go:generate for staticcheck (#59215)

Closes https://github.com/sourcegraph/sourcegraph/issues/54833

## Test plan

`bazel run //dev/linters/staticcheck:write_generated_bazelfile` and `cd dev/linters/staticcheck && go generate` as well as adding staticchecks to be ignored

dev/BUILD.bazel

@@ -24,5 +24,6 @@ write_source_files(
         "//migrations/codeintel:write_squashed",
         "//migrations/frontend:write_squashed",
         "//schema:write_generated_schema",
+        "//dev/linters/staticcheck:write_generated_bazelfile",
     ],
 )

dev/linters/staticcheck/cmd/gen.go

@@ -23,37 +23,29 @@ var BazelBuildTemplate = `# GENERATED FILE - DO NOT EDIT
 # This file was generated by running go generate on dev/linters/staticcheck
 #
 # If you want to ignore an analyzer add it to the ignore list in dev/linters/staticcheck/cmd/gen.go,
-# and re-run go generate
+# and re-run go generate.
+#
+# IMPORTANT: Starlark is spaces/tabs sensitive, make sure the below is SPACE indented.
 
 load("@io_bazel_rules_go//go:def.bzl", "go_library")
-{{ range .Analyzers}}
-go_library(
-    name = "{{.Analyzer.Name}}",
-    srcs = ["staticcheck.go"],
-    importpath = "github.com/sourcegraph/sourcegraph/dev/linters/staticcheck/{{.Analyzer.Name}}",
-    visibility = ["//visibility:public"],
-    x_defs = {"AnalyzerName": "{{.Analyzer.Name}}"},
-    deps = [
-        "//dev/linters/nolint",
-        "@co_honnef_go_tools//analysis/lint",
-        "@co_honnef_go_tools//simple",
-        "@co_honnef_go_tools//staticcheck",
-        "@org_golang_x_tools//go/analysis",
-    ],
-)
-{{ end}}
-go_library(
-    name = "staticcheck",
-    srcs = ["staticcheck.go"],
-    importpath = "github.com/sourcegraph/sourcegraph/dev/linters/staticcheck",
-    visibility = ["//visibility:public"],
-    deps = [
-        "//dev/linters/nolint",
-        "@co_honnef_go_tools//simple",
-        "@co_honnef_go_tools//staticcheck",
-        "@org_golang_x_tools//go/analysis",
-    ],
-)
+
+def staticcheck_targets():
+{{ range .Analyzers }}    go_library(
+        name = "{{.Analyzer.Name}}",
+        srcs = ["staticcheck.go"],
+        importpath = "github.com/sourcegraph/sourcegraph/dev/linters/staticcheck/{{.Analyzer.Name}}",
+        visibility = ["//visibility:public"],
+        x_defs = {"AnalyzerName": "{{.Analyzer.Name}}"},
+        deps = [
+            "//dev/linters/nolint",
+            "@co_honnef_go_tools//analysis/lint",
+            "@co_honnef_go_tools//simple",
+            "@co_honnef_go_tools//staticcheck",
+            "@org_golang_x_tools//go/analysis",
+        ],
+    )
+
+{{ end -}}
 `
 
 var BazelDefTemplate = `# DO NOT EDIT - this file was generated by running go generate on dev/linters/staticcheck
@@ -62,9 +54,9 @@ var BazelDefTemplate = `# DO NOT EDIT - this file was generated by running go ge
 # and re-run go generate
 
 STATIC_CHECK_ANALYZERS = [
-{{- range .Analyzers}}
+{{- range .Analyzers }}
     "//dev/linters/staticcheck:{{.Analyzer.Name}}",
-{{- end}}
+{{- end }}
 ]
 `
 
@@ -108,7 +100,7 @@ func writeTemplate(targetFile, templateDef string) error {
 	name := targetFile
 	tmpl := template.Must(template.New(name).Parse(templateDef))
 
-	f, err := os.OpenFile(targetFile, os.O_CREATE|os.O_TRUNC|os.O_RDWR, 0666)
+	f, err := os.OpenFile(targetFile, os.O_CREATE|os.O_TRUNC|os.O_RDWR, 0o666)
 	if err != nil {
 		return err
 	}
@@ -130,7 +122,7 @@ func writeTemplate(targetFile, templateDef string) error {
 // 1: buildfile path - file where the analyzer targets should be generated to
 // 2: analyzer definition path - file where a convienience analyzer array is generated that contains all the targets
 func main() {
-	targetFile := "BUILD.bazel"
+	targetFile := "targets.bzl"
 	if len(os.Args) > 1 {
 		targetFile = os.Args[1]
 	}
@@ -150,5 +142,4 @@ func main() {
 		fmt.Fprintln(os.Stderr, "failed to render Anazlyers definiton template")
 		panic(err)
 	}
-
 }

dev/linters/staticcheck/staticcheck.go

@@ -1,4 +1,5 @@
-//go:generate go run ./cmd/gen.go BUILD.bazel
+//go:generate go run ./cmd/gen.go targets.bzl
+//go:generate truncate -s -1 targets.bzl
 package staticcheck
 
 import (
@@ -12,8 +13,10 @@ import (
 // AllAnalyzers contains staticcheck and gosimple Analyzers
 var AllAnalyzers = append(staticcheck.Analyzers, simple.Analyzers...)
 
-var AnalyzerName = ""
-var Analyzer *analysis.Analyzer = GetAnalyzerByName(AnalyzerName)
+var (
+	AnalyzerName                    = ""
+	Analyzer     *analysis.Analyzer = GetAnalyzerByName(AnalyzerName)
+)
 
 func GetAnalyzerByName(name string) *analysis.Analyzer {
 	for _, a := range AllAnalyzers {