hcled: Introduce ContextDefRange (#58)

This can be used for looking up range of block definition
so that we can render it alongside attribute-agnostic errors

hcl/hclsyntax/navigation.go

@@ -3,6 +3,8 @@ package hclsyntax
 import (
 	"bytes"
 	"fmt"
+
+	"github.com/hashicorp/hcl2/hcl"
 )
 
 type navigation struct {
@@ -39,3 +41,19 @@ func (n navigation) ContextString(offset int) string {
 	}
 	return buf.String()
 }
+
+func (n navigation) ContextDefRange(offset int) hcl.Range {
+	var block *Block
+	for _, candidate := range n.root.Blocks {
+		if candidate.Range().ContainsOffset(offset) {
+			block = candidate
+			break
+		}
+	}
+
+	if block == nil {
+		return hcl.Range{}
+	}
+
+	return block.DefRange()
+}

hcl/hclsyntax/navigation_test.go

@@ -0,0 +1,133 @@
+package hclsyntax
+
+import (
+	"fmt"
+	"strconv"
+	"testing"
+
+	"github.com/hashicorp/hcl2/hcl"
+)
+
+func TestNavigationContextString(t *testing.T) {
+	cfg := `
+
+
+resource {
+}
+
+resource "random_type" {
+}
+
+resource "null_resource" "baz" {
+  name = "foo"
+  boz = {
+  	one = "111"
+  	two = "22222"
+  }
+}
+
+data "another" "baz" {
+  name = "foo"
+  boz = {
+  	one = "111"
+  	two = "22222"
+  }
+}
+`
+	file, diags := ParseConfig([]byte(cfg), "", hcl.Pos{Byte: 0, Line: 1, Column: 1})
+	if len(diags) != 0 {
+		fmt.Printf("offset %d\n", diags[0].Subject.Start.Byte)
+		t.Errorf("Unexpected diagnostics: %s", diags)
+	}
+	if file == nil {
+		t.Fatalf("Got nil file")
+	}
+	nav := file.Nav.(navigation)
+
+	testCases := []struct {
+		Offset int
+		Want   string
+	}{
+		{0, ``},
+		{2, ``},
+		{4, `resource`},
+		{17, `resource "random_type"`},
+		{25, `resource "random_type"`},
+		{45, `resource "null_resource" "baz"`},
+		{142, `data "another" "baz"`},
+		{180, `data "another" "baz"`},
+		{99999, ``},
+	}
+
+	for _, tc := range testCases {
+		t.Run(strconv.Itoa(tc.Offset), func(t *testing.T) {
+			got := nav.ContextString(tc.Offset)
+
+			if got != tc.Want {
+				t.Errorf("wrong result\ngot:  %s\nwant: %s", got, tc.Want)
+			}
+		})
+	}
+}
+
+func TestNavigationContextDefRange(t *testing.T) {
+	cfg := `
+
+
+resource {
+}
+
+resource "random_type" {
+}
+
+resource "null_resource" "baz" {
+  name = "foo"
+  boz = {
+  	one = "111"
+  	two = "22222"
+  }
+}
+
+data "another" "baz" {
+  name = "foo"
+  boz = {
+  	one = "111"
+  	two = "22222"
+  }
+}
+`
+	file, diags := ParseConfig([]byte(cfg), "", hcl.Pos{Byte: 0, Line: 1, Column: 1})
+	if len(diags) != 0 {
+		fmt.Printf("offset %d\n", diags[0].Subject.Start.Byte)
+		t.Errorf("Unexpected diagnostics: %s", diags)
+	}
+	if file == nil {
+		t.Fatalf("Got nil file")
+	}
+	nav := file.Nav.(navigation)
+
+	testCases := []struct {
+		Offset    int
+		WantRange hcl.Range
+	}{
+		{0, hcl.Range{}},
+		{2, hcl.Range{}},
+		{4, hcl.Range{Filename: "", Start: hcl.Pos{Line: 4, Column: 1, Byte: 3}, End: hcl.Pos{Line: 4, Column: 11, Byte: 13}}},
+		{17, hcl.Range{Filename: "", Start: hcl.Pos{Line: 7, Column: 1, Byte: 17}, End: hcl.Pos{Line: 7, Column: 25, Byte: 41}}},
+		{25, hcl.Range{Filename: "", Start: hcl.Pos{Line: 7, Column: 1, Byte: 17}, End: hcl.Pos{Line: 7, Column: 25, Byte: 41}}},
+		{45, hcl.Range{Filename: "", Start: hcl.Pos{Line: 10, Column: 1, Byte: 45}, End: hcl.Pos{Line: 10, Column: 33, Byte: 77}}},
+		{142, hcl.Range{Filename: "", Start: hcl.Pos{Line: 18, Column: 1, Byte: 142}, End: hcl.Pos{Line: 18, Column: 23, Byte: 164}}},
+		{180, hcl.Range{Filename: "", Start: hcl.Pos{Line: 18, Column: 1, Byte: 142}, End: hcl.Pos{Line: 18, Column: 23, Byte: 164}}},
+		{99999, hcl.Range{}},
+	}
+
+	for _, tc := range testCases {
+		t.Run(strconv.Itoa(tc.Offset), func(t *testing.T) {
+			got := nav.ContextDefRange(tc.Offset)
+
+			if got != tc.WantRange {
+				t.Errorf("wrong range\ngot:  %#v\nwant: %#v", got, tc.WantRange)
+			}
+		})
+	}
+}

hcl/hclsyntax/structure.go

@@ -384,3 +384,7 @@ func (b *Block) walkChildNodes(w internalWalkFunc) {
 func (b *Block) Range() hcl.Range {
 	return hcl.RangeBetween(b.TypeRange, b.CloseBraceRange)
 }
+
+func (b *Block) DefRange() hcl.Range {
+	return hcl.RangeBetween(b.TypeRange, b.OpenBraceRange)
+}

hcled/navigation.go

@@ -18,3 +18,17 @@ func ContextString(file *hcl.File, offset int) string {
 	}
 	return ""
 }
+
+type contextDefRanger interface {
+	ContextDefRange(offset int) hcl.Range
+}
+
+func ContextDefRange(file *hcl.File, offset int) hcl.Range {
+	if cser, ok := file.Nav.(contextDefRanger); ok {
+		defRange := cser.ContextDefRange(offset)
+		if !defRange.Empty() {
+			return defRange
+		}
+	}
+	return file.Body.MissingItemRange()
+}