Merge pull request #2448 from alixander/fix-classes-panic

d2ir: fix classes panic

ci/release/changelogs/next.md

@@ -25,6 +25,7 @@
   - fixes panic when comment lines appear in arrays [#2378](https://github.com/terrastruct/d2/pull/2378)
   - fixes inconsistencies when objects were double quoted [#2390](https://github.com/terrastruct/d2/pull/2390)
   - fixes globs not applying to spread substitutions [#2426](https://github.com/terrastruct/d2/issues/2426)
+  - fixes panic when classes were mixed with layers incorrectly [#2448](https://github.com/terrastruct/d2/pull/2448)
 - CLI: fetch and render remote images of mimetype octet-stream correctly [#2370](https://github.com/terrastruct/d2/pull/2370)
 - d2js: handle unicode characters [#2393](https://github.com/terrastruct/d2/pull/2393)
 

d2compiler/compile_test.go

@@ -328,7 +328,7 @@ containers: {
   Steps
 }
 `,
-			expErr: `d2/testdata/d2compiler/TestCompile/image_children_Steps.d2:4:3: steps is only allowed at a board root`,
+			expErr: `d2/testdata/d2compiler/TestCompile/image_children_Steps.d2:4:3: steps must be declared at a board root scope`,
 		},
 		{
 			name: "name-with-dot-underscore",
@@ -1714,6 +1714,40 @@ steps: {
 				assert.Equal(t, 1, len(g.Layers[0].Steps))
 			},
 		},
+		{
+			name: "import-classes-boards",
+
+			text: `classes: {
+  a: {
+		label: hi
+  }
+}
+
+layers: {
+  asdf: {
+    qwer: {
+      layers: {
+        ok: {
+          bok
+				}
+      }
+    }
+  }
+  wert: {
+    classes: @classes
+  }
+}
+
+`,
+			files: map[string]string{
+				"classes.d2": `
+c: {
+	label: bye
+}
+`,
+			},
+			expErr: `d2/testdata/d2compiler/TestCompile/import-classes-boards.d2:10:7: layers must be declared at a board root scope`,
+		},
 		{
 			name: "import_url_link",
 

d2ir/compile.go

@@ -113,7 +113,7 @@ func (c *compiler) overlayClasses(m *Map) {
 		if lClasses == nil {
 			lClasses = classes.Copy(l).(*Field)
 			l.Fields = append(l.Fields, lClasses)
-		} else {
+		} else if lClasses.Map() != nil {
 			base := classes.Copy(l).(*Field)
 			OverlayMap(base.Map(), lClasses.Map())
 			l.DeleteField("classes")

d2ir/compile_test.go

@@ -593,7 +593,7 @@ classes: {
   }
 }
 `)
-				assert.ErrorString(t, err, `TestCompile/classes/nonroot.d2:2:3: classes is only allowed at a board root`)
+				assert.ErrorString(t, err, `TestCompile/classes/nonroot.d2:2:3: classes must be declared at a board root scope`)
 			},
 		},
 		{

d2ir/d2ir.go

@@ -942,11 +942,11 @@ func (m *Map) ensureField(i int, kp *d2ast.KeyPath, refctx *RefContext, create b
 	}
 
 	if headString == "classes" && head.IsUnquoted() && NodeBoardKind(m) == "" {
-		return d2parser.Errorf(kp.Path[i].Unbox(), "%s is only allowed at a board root", headString)
+		return d2parser.Errorf(kp.Path[i].Unbox(), "%s must be declared at a board root scope", headString)
 	}
 
 	if findBoardKeyword(head) != -1 && head.IsUnquoted() && NodeBoardKind(m) == "" {
-		return d2parser.Errorf(kp.Path[i].Unbox(), "%s is only allowed at a board root", headString)
+		return d2parser.Errorf(kp.Path[i].Unbox(), "%s must be declared at a board root scope", headString)
 	}
 
 	for _, f := range m.Fields {

testdata/d2compiler/TestCompile/image_children_Steps.exp.json

@@ -4,7 +4,7 @@
     "errs": [
       {
         "range": "d2/testdata/d2compiler/TestCompile/image_children_Steps.d2,3:2:115-3:7:120",
-        "errmsg": "d2/testdata/d2compiler/TestCompile/image_children_Steps.d2:4:3: steps is only allowed at a board root"
+        "errmsg": "d2/testdata/d2compiler/TestCompile/image_children_Steps.d2:4:3: steps must be declared at a board root scope"
       }
     ]
   }

testdata/d2compiler/TestCompile/import-classes-boards.exp.json

@@ -0,0 +1,11 @@
+{
+  "graph": null,
+  "err": {
+    "errs": [
+      {
+        "range": "d2/testdata/d2compiler/TestCompile/import-classes-boards.d2,9:6:75-9:12:81",
+        "errmsg": "d2/testdata/d2compiler/TestCompile/import-classes-boards.d2:10:7: layers must be declared at a board root scope"
+      }
+    ]
+  }
+}