fix(3242): check class name collisions with Object

Author: a-tarasyuk

internal/checker/checker.go

@@ -6718,6 +6718,12 @@ func (c *Checker) checkTypeNameIsReserved(name *ast.Node, message *diagnostics.M
 	}
 }
 
+func (c *Checker) checkClassNameCollisionWithObject(name *ast.Node) {
+	if name.Text() == "Object" && c.program.GetEmitModuleFormatOfFile(ast.GetSourceFileOfNode(name)) < core.ModuleKindES2015 {
+		c.error(name, diagnostics.Class_name_cannot_be_Object_when_targeting_ES5_and_above_with_module_0, c.moduleKind.String())
+	}
+}
+
 func (c *Checker) checkExportsOnMergedDeclarations(node *ast.Node) {
 	// If localSymbol is defined on node then node itself is exported - check is required.
 	symbol := node.LocalSymbol()
@@ -10175,7 +10181,12 @@ func (c *Checker) checkCollisionsForDeclarationName(node *ast.Node, name *ast.No
 	case name == nil:
 		return
 	case ast.IsClassLike(node):
-		c.checkTypeNameIsReserved(name, diagnostics.Class_name_cannot_be_0)
+		{
+			c.checkTypeNameIsReserved(name, diagnostics.Class_name_cannot_be_0)
+			if node.Flags&ast.NodeFlagsAmbient != 0 {
+				c.checkClassNameCollisionWithObject(name)
+			}
+		}
 	case ast.IsEnumDeclaration(node):
 		c.checkTypeNameIsReserved(name, diagnostics.Enum_name_cannot_be_0)
 	}

testdata/baselines/reference/submodule/conformance/exportAmbientClassNameWithObject(target=es2015).errors.txt

@@ -0,0 +1,8 @@
+exportAmbientClassNameWithObject.ts(1,22): error TS2725: Class name cannot be 'Object' when targeting ES5 and above with module CommonJS.
+
+
+==== exportAmbientClassNameWithObject.ts (1 errors) ====
+    export declare class Object {}
+                         ~~~~~~
+!!! error TS2725: Class name cannot be 'Object' when targeting ES5 and above with module CommonJS.
+    

testdata/baselines/reference/submodule/conformance/exportAmbientClassNameWithObject(target=es2015).errors.txt.diff

@@ -0,0 +1,12 @@
+--- old.exportAmbientClassNameWithObject(target=es2015).errors.txt
++++ new.exportAmbientClassNameWithObject(target=es2015).errors.txt
+@@= skipped -0, +0 lines =@@
+-<no content>
++exportAmbientClassNameWithObject.ts(1,22): error TS2725: Class name cannot be 'Object' when targeting ES5 and above with module CommonJS.
++
++
++==== exportAmbientClassNameWithObject.ts (1 errors) ====
++    export declare class Object {}
++                         ~~~~~~
++!!! error TS2725: Class name cannot be 'Object' when targeting ES5 and above with module CommonJS.
++