Add a test for swift call site breakpoint and stepping.

Author: jimingham

lldb/test/API/lang/swift/macro/Macro.swift

@@ -1 +1,3 @@
 @freestanding(expression) public macro stringify<T>(_ value: T) -> (T, String) = #externalMacro(module: "MacroImpl", type: "StringifyMacro")
+
+@freestanding(expression) public macro no_return<T>(_ value: T) = #externalMacro(module: "MacroImpl", type: "NoReturnMacro")

lldb/test/API/lang/swift/macro/MacroImpl.swift

@@ -14,3 +14,16 @@ public struct StringifyMacro: ExpressionMacro {
     return "(\(argument), \(StringLiteralExprSyntax(content: argument.description)))"
   }
 }
+
+public struct NoReturnMacro: ExpressionMacro {
+  public static func expansion(
+    of macro: some FreestandingMacroExpansionSyntax,
+    in context: some MacroExpansionContext
+  ) -> ExprSyntax {
+    guard let argument = macro.argumentList.first?.expression else {
+      fatalError("boom")
+    }
+
+    return "print(\(argument), \(StringLiteralExprSyntax(content: argument.description)))"
+  }
+}

lldb/test/API/lang/swift/macro/TestSwiftMacro.py

@@ -34,19 +34,58 @@ def testDebugging(self):
         """Test Swift macros"""
         self.build(dictionary={'SWIFT_SOURCES': 'main.swift'})
         self.setupPluginServerForTesting()
+        main_spec = lldb.SBFileSpec('main.swift')
         target, process, thread, bkpt = lldbutil.run_to_source_breakpoint(
-            self, 'break here', lldb.SBFileSpec('main.swift'))
+            self, 'break here', main_spec
+        )
+
+        # We're testing line breakpoint setting here:
+        call_site_line = lldbtest.line_number("main.swift", "#no_return(a / b)")
+        call_site_bp = target.BreakpointCreateByLocation(main_spec, call_site_line)
 
         thread.StepOver()
         thread.StepInto()
+        
         # This is the expanded macro source, we should be able to step into it.
-        self.expect('reg read pc', substrs=[
-            '[inlined] freestanding macro expansion #1 of stringify in module a file main.swift line 5 column 11',
-            'stringify'
-        ])
+        # Don't check the actual line number so we are line independent
+        self.assertIn(
+            'freestanding macro expansion #1 of stringify in module a file main.swift line 5 column 11',
+            thread.frames[0].name,
+            "Stopped in stringify macro"
+        )
 
         self.expect('expression -- #stringify(1)', substrs=['0 = 1', '1 = "1"'])
 
+        # Step out should get us out of stringify, then in to the next macro:
+        thread.StepOut()
+        self.assertIn("a.testStringify", thread.frames[0].name, "Step out back to origin")
+        thread.StepInto()
+        self.assertIn(
+            "freestanding macro expansion #1 of no_return in module a file main.swift line 6 column 3",
+            thread.frames[0].name,
+            "Step out and in gets to no_return"
+        )
+        
+        # We've set a breakpoint on the call site for another instance - run to that:
+        threads = lldbutil.continue_to_breakpoint(process, call_site_bp)
+        self.assertEqual(len(threads), 1, "Stopped at one thread")
+        thread = threads[0]
+        frame_0 = thread.frames[0]
+        line_entry_0 = frame_0.line_entry
+        self.assertEqual(line_entry_0.line, call_site_line, "Got the right line attribution")
+        self.assertEqual(line_entry_0.file, main_spec, "Got the right file attribution") 
+
+        # Now test stepping in and back out again:
+        thread.StepInto()
+        self.assertIn(
+            "freestanding macro expansion #3 of no_return in module a file main.swift line 8 column 3",
+            thread.frames[0].name,
+            "Step out and in gets to no_return"
+        )
+        
+        thread.StepOut()
+        self.assertIn("a.testStringify", thread.frames[0].name, "Step out from no_return")
+        
         # Make sure we can set a symbolic breakpoint on a macro.
         b = target.BreakpointCreateByName("stringify")
         self.assertGreaterEqual(b.GetNumLocations(), 1)

lldb/test/API/lang/swift/macro/main.swift

@@ -1,9 +1,12 @@
 import Macro
-
+// This test depends on the layout of the lines in this file.
 func testStringify(a: Int, b: Int) {
   print("break here")
   let s = #stringify(a / b)
+  #no_return(a)
+  #no_return(b)
+  #no_return(a / b)
   print(s.1)
 }
 
-testStringify(a: 23, b: 0)
+testStringify(a: 23, b: 1)