implement expression conversions via BzlExprValue interface (bazel-co…

…ntrib#1714) * label: implement BzlExprValue * rule: GlobValue: implement BzlExprValue
spags-lacework · Jan 4, 2024 · 5ca287b · 5ca287b
1 parent e7e69c4
commit 5ca287b
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Showing 3 changed files with 28 additions and 23 deletions.
diff --git a/label/BUILD.bazel b/label/BUILD.bazel
@@ -5,7 +5,10 @@ go_library(
     srcs = ["label.go"],
     importpath = "github.com/bazelbuild/bazel-gazelle/label",
     visibility = ["//visibility:public"],
-    deps = ["//pathtools"],
+    deps = [
+        "//pathtools",
+        "@com_github_bazelbuild_buildtools//build",
+    ],
 )
 
 go_test(

diff --git a/label/label.go b/label/label.go
@@ -27,6 +27,7 @@ import (
 	"strings"
 
 	"github.com/bazelbuild/bazel-gazelle/pathtools"
+	bzl "github.com/bazelbuild/buildtools/build"
 )
 
 // A Label represents a label of a build target in Bazel. Labels have three
@@ -210,6 +211,12 @@ func (l Label) Contains(other Label) bool {
 	return result
 }
 
+func (l Label) BzlExpr() bzl.Expr {
+	return &bzl.StringExpr {
+	    Value: l.String(),
+	}
+}
+
 var nonWordRe = regexp.MustCompile(`\W+`)
 
 // ImportPathToBazelRepoName converts a Go import path into a bazel repo name

diff --git a/rule/value.go b/rule/value.go
@@ -22,7 +22,6 @@ import (
 	"sort"
 
 	bzl "github.com/bazelbuild/buildtools/build"
-	"github.com/bazelbuild/bazel-gazelle/label"
 )
 
 // KeyValue represents a key-value pair. This gets converted into a
@@ -38,6 +37,23 @@ type GlobValue struct {
 	Excludes []string
 }
 
+func (g GlobValue) BzlExpr() bzl.Expr {
+	patternsValue := ExprFromValue(g.Patterns)
+	globArgs := []bzl.Expr{patternsValue}
+	if len(g.Excludes) > 0 {
+		excludesValue := ExprFromValue(g.Excludes)
+		globArgs = append(globArgs, &bzl.AssignExpr{
+			LHS: &bzl.LiteralExpr{Token: "exclude"},
+			Op:  "=",
+			RHS: excludesValue,
+		})
+	}
+	return &bzl.CallExpr{
+		X:    &bzl.LiteralExpr{Token: "glob"},
+		List: globArgs,
+	}
+}
+
 // BzlExprValue is implemented by types that have custom translations
 // to Starlark values.
 type BzlExprValue interface {
@@ -182,27 +198,6 @@ func ExprFromValue(val interface{}) bzl.Expr {
 			args[i] = &bzl.KeyValueExpr{Key: k, Value: v}
 		}
 		return &bzl.DictExpr{List: args, ForceMultiLine: true}
-
-	case reflect.Struct:
-		switch val := val.(type) {
-		case GlobValue:
-			patternsValue := ExprFromValue(val.Patterns)
-			globArgs := []bzl.Expr{patternsValue}
-			if len(val.Excludes) > 0 {
-				excludesValue := ExprFromValue(val.Excludes)
-				globArgs = append(globArgs, &bzl.AssignExpr{
-					LHS: &bzl.LiteralExpr{Token: "exclude"},
-					Op:  "=",
-					RHS: excludesValue,
-				})
-			}
-			return &bzl.CallExpr{
-				X:    &bzl.LiteralExpr{Token: "glob"},
-				List: globArgs,
-			}
-		case label.Label:
-			return &bzl.StringExpr{Value: val.String()}
-		}
 	}
 
 	log.Panicf("type not supported: %T", val)