Normalization of configuration paths

command/meta.go

@@ -266,6 +266,10 @@ func (m *Meta) StdinPiped() bool {
 // operation itself is unsuccessful. Use the "Result" field of the
 // returned operation object to recognize operation-level failure.
 func (m *Meta) RunOperation(b backend.Enhanced, opReq *backend.Operation) (*backend.RunningOperation, error) {
+	if opReq.ConfigDir != "" {
+		opReq.ConfigDir = m.normalizePath(opReq.ConfigDir)
+	}
+
 	op, err := b.Operation(context.Background(), opReq)
 	if err != nil {
 		return nil, fmt.Errorf("error starting operation: %s", err)

terraform/evaluate.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"log"
 	"os"
+	"path/filepath"
 	"strconv"
 	"sync"
 
@@ -423,7 +424,7 @@ func (d *evaluationStateData) GetPathAttr(addr addrs.PathAttr, rng tfdiags.Sourc
 			})
 			return cty.DynamicVal, diags
 		}
-		return cty.StringVal(wd), diags
+		return cty.StringVal(filepath.ToSlash(wd)), diags
 
 	case "module":
 		moduleConfig := d.Evaluator.Config.DescendentForInstance(d.ModulePath)
@@ -433,11 +434,11 @@ func (d *evaluationStateData) GetPathAttr(addr addrs.PathAttr, rng tfdiags.Sourc
 			panic(fmt.Sprintf("module.path read from module %s, which has no configuration", d.ModulePath))
 		}
 		sourceDir := moduleConfig.Module.SourceDir
-		return cty.StringVal(sourceDir), diags
+		return cty.StringVal(filepath.ToSlash(sourceDir)), diags
 
 	case "root":
 		sourceDir := d.Evaluator.Config.Module.SourceDir
-		return cty.StringVal(sourceDir), diags
+		return cty.StringVal(filepath.ToSlash(sourceDir)), diags
 
 	default:
 		suggestion := nameSuggestion(addr.Name, []string{"cwd", "module", "root"})

terraform/evaluate_test.go

@@ -7,6 +7,7 @@ import (
 	"github.com/zclconf/go-cty/cty"
 
 	"github.com/hashicorp/terraform/addrs"
+	"github.com/hashicorp/terraform/configs"
 	"github.com/hashicorp/terraform/tfdiags"
 )
 
@@ -34,3 +35,46 @@ func TestEvaluatorGetTerraformAttr(t *testing.T) {
 		}
 	})
 }
+
+func TestEvaluatorGetPathAttr(t *testing.T) {
+	evaluator := &Evaluator{
+		Meta: &ContextMeta{
+			Env: "foo",
+		},
+		Config: &configs.Config{
+			Module: &configs.Module{
+				SourceDir: "bar/baz",
+			},
+		},
+	}
+	data := &evaluationStateData{
+		Evaluator: evaluator,
+	}
+	scope := evaluator.Scope(data, nil)
+
+	t.Run("module", func(t *testing.T) {
+		want := cty.StringVal("bar/baz")
+		got, diags := scope.Data.GetPathAttr(addrs.PathAttr{
+			Name: "module",
+		}, tfdiags.SourceRange{})
+		if len(diags) != 0 {
+			t.Errorf("unexpected diagnostics %s", spew.Sdump(diags))
+		}
+		if !got.RawEquals(want) {
+			t.Errorf("wrong result %#v; want %#v", got, want)
+		}
+	})
+
+	t.Run("root", func(t *testing.T) {
+		want := cty.StringVal("bar/baz")
+		got, diags := scope.Data.GetPathAttr(addrs.PathAttr{
+			Name: "root",
+		}, tfdiags.SourceRange{})
+		if len(diags) != 0 {
+			t.Errorf("unexpected diagnostics %s", spew.Sdump(diags))
+		}
+		if !got.RawEquals(want) {
+			t.Errorf("wrong result %#v; want %#v", got, want)
+		}
+	})
+}