diff --git a/tests/expectations/opaque.zig b/tests/expectations/opaque.zig
index 95a0b682a..7aa8c07f3 100644
--- a/tests/expectations/opaque.zig
+++ b/tests/expectations/opaque.zig
@@ -1 +1,14 @@
 const std = @import("std");
+
+const HashMap_i32__i32__BuildHasherDefault_DefaultHasher = opaque {};
+
+const Result_Foo = opaque {};
+
+/// Fast hash map used internally.
+pub const FastHashMap_i32__i32 = HashMap_i32__i32__BuildHasherDefault_DefaultHasher;
+
+pub const Foo = FastHashMap_i32__i32;
+
+pub const Bar = Result_Foo;
+
+pub extern fn root(a: ?*Foo, b: ?*Bar) anyopaque;
diff --git a/tests/expectations/pin.zig b/tests/expectations/pin.zig
index 7e0594944..161d81bfa 100644
--- a/tests/expectations/pin.zig
+++ b/tests/expectations/pin.zig
@@ -5,4 +5,4 @@ pub const PinTest = extern struct {
     _pinned_ref: ?*i32,
 };
 
-extern fn root(_s: ?*i32, p: PinTest) anyopaque;
+pub extern fn root(_s: ?*i32, p: PinTest) anyopaque;
diff --git a/tests/expectations/pragma_once.zig b/tests/expectations/pragma_once.zig
index 95a0b682a..d4c2e15c7 100644
--- a/tests/expectations/pragma_once.zig
+++ b/tests/expectations/pragma_once.zig
@@ -1 +1,3 @@
 const std = @import("std");
+
+pub extern fn root() anyopaque;
diff --git a/tests/expectations/prefixed_struct_literal_deep.zig b/tests/expectations/prefixed_struct_literal_deep.zig
index 95a0b682a..8bdf63994 100644
--- a/tests/expectations/prefixed_struct_literal_deep.zig
+++ b/tests/expectations/prefixed_struct_literal_deep.zig
@@ -1 +1,20 @@
 const std = @import("std");
+
+pub const PREFIXBar = extern struct {
+    a: i32,
+};
+pub const PREFIXFoo = extern struct {
+    a: i32,
+    b: u32,
+    bar: PREFIXBar,
+};
+
+pub extern fn root(x: PREFIXFoo) anyopaque;
+
+pub const PREFIXVAL = @import("std").mem.zeroInit(PREFIXFoo, .{
+    .a = @as(c_int, 42),
+    .b = @as(c_int, 1337),
+    .bar = @import("std").mem.zeroInit(PREFIXBar, .{
+        .a = @as(c_int, 323),
+    }),
+});
diff --git a/tests/expectations/rename_crate.zig b/tests/expectations/rename_crate.zig
new file mode 100644
index 000000000..ba040f389
--- /dev/null
+++ b/tests/expectations/rename_crate.zig
@@ -0,0 +1,20 @@
+const std = @import("std");
+
+pub const Foo = extern struct {
+    x: i32,
+};
+pub const RenamedTy = extern struct {
+    y: u64,
+};
+pub const NoExternTy = extern struct {
+    field: u8,
+};
+pub const ContainsNoExternTy = extern struct {
+    field: NoExternTy,
+};
+
+pub extern fn root(a: Foo) anyopaque;
+
+pub extern fn renamed_func(a: RenamedTy) anyopaque;
+
+pub extern fn no_extern_func(a: ContainsNoExternTy) anyopaque;
diff --git a/tests/expectations/rename_crates.zig b/tests/expectations/rename_crates.zig
deleted file mode 100644
index 95a0b682a..000000000
--- a/tests/expectations/rename_crates.zig
+++ /dev/null
@@ -1 +0,0 @@
-const std = @import("std");
diff --git a/tests/expectations/renaming_overrides_prefixing.zig b/tests/expectations/renaming_overrides_prefixing.zig
index 95a0b682a..72dace5fc 100644
--- a/tests/expectations/renaming_overrides_prefixing.zig
+++ b/tests/expectations/renaming_overrides_prefixing.zig
@@ -1 +1,12 @@
 const std = @import("std");
+
+const A = opaque {
+
+};
+
+pub const B = extern struct {
+  x: i32,
+  y: f32,
+};
+
+pub extern fn root( a: ?*A, b: B) anyopaque;
diff --git a/tests/expectations/sentinel.zig b/tests/expectations/sentinel.zig
index 95a0b682a..409ea7932 100644
--- a/tests/expectations/sentinel.zig
+++ b/tests/expectations/sentinel.zig
@@ -1 +1,37 @@
 const std = @import("std");
+
+pub const A = enum {
+  A1,
+  A2,
+  A3,
+};
+
+pub const B = enum {
+  B1,
+  B2,
+  B3,
+};
+
+pub const C_Tag = enum {
+  C1,
+  C2,
+  C3,
+};
+
+pub const C1_Body = extern struct {
+  tag: C_Tag,
+  a: u32,
+};
+
+pub const C2_Body = extern struct {
+  tag: C_Tag,
+  b: u32,
+};
+
+pub const C = extern union {
+  tag: C_Tag,
+  c1: C1_Body,
+  c2: C2_Body,
+};
+
+pub extern fn root(a: A, b: B, c: C) anyopaque;
diff --git a/tests/expectations/simplify_option_ptr.zig b/tests/expectations/simplify_option_ptr.zig
index 95a0b682a..1f9e5c82b 100644
--- a/tests/expectations/simplify_option_ptr.zig
+++ b/tests/expectations/simplify_option_ptr.zig
@@ -1 +1,20 @@
 const std = @import("std");
+
+pub const Opaque = opaque {};
+pub const Option_____Opaque = opaque {};
+
+pub const Foo = extern struct {
+    x: ?*const Opaque,
+    y: ?*Opaque,
+    z: ?*const fn () anyopaque,
+    zz: [*]?*const fn () anyopaque,
+};
+
+pub const Bar = extern union {
+    x: ?*const Opaque,
+    y: ?*Opaque,
+    z: ?*const fn () anyopaque,
+    zz: [*]?*const fn () anyopaque,
+};
+
+pub extern fn root(a: ?*const Opaque, b: ?*Opaque, c: Foo, d: Bar, e: ?*Option_____Opaque, f: ?*const fn (?*const Opaque) anyopaque) anyopaque;
diff --git a/tests/expectations/size_types.zig b/tests/expectations/size_types.zig
index 95a0b682a..e0cd28725 100644
--- a/tests/expectations/size_types.zig
+++ b/tests/expectations/size_types.zig
@@ -1 +1,15 @@
 const std = @import("std");
+
+pub const IE = enum {
+    IV,
+};
+
+pub const UE = enum {
+    UV,
+};
+
+pub const Usize = usize;
+
+pub const Isize = isize;
+
+pub extern fn root(Usize, Isize, UE, IE) anyopaque;
diff --git a/tests/expectations/static.zig b/tests/expectations/static.zig
index 95a0b682a..1b2ebcccb 100644
--- a/tests/expectations/static.zig
+++ b/tests/expectations/static.zig
@@ -1 +1,13 @@
 const std = @import("std");
+
+const Bar = opaque {};
+
+pub const Foo = extern struct {};
+
+pub extern const NUMBER: i32;
+
+pub extern const FOO: Foo;
+
+pub extern const BAR: Bar;
+
+pub extern fn root() anyopaque;
diff --git a/tests/expectations/std_lib.zig b/tests/expectations/std_lib.zig
index 95a0b682a..5af07d1ff 100644
--- a/tests/expectations/std_lib.zig
+++ b/tests/expectations/std_lib.zig
@@ -1 +1,9 @@
 const std = @import("std");
+
+const Option_i32 = opaque {};
+
+const Result_i32__String = opaque {};
+
+const Vec_String = opaque {};
+
+pub extern fn root(a: ?*Vec_String, b: ?*Option_i32, c: ?*Result_i32__String) anyopaque;
diff --git a/tests/expectations/struct.zig b/tests/expectations/struct.zig
index 95a0b682a..b14ced846 100644
--- a/tests/expectations/struct.zig
+++ b/tests/expectations/struct.zig
@@ -1 +1,31 @@
 const std = @import("std");
+
+const Opaque = opaque {
+
+};
+
+pub const Normal = extern struct {
+  x: i32,
+  y: f32,
+};
+
+pub const NormalWithZST = extern struct {
+  x: i32,
+  y: f32,
+};
+
+pub const TupleRenamed = extern struct {
+  m0: i32,
+  m1: f32,
+};
+
+pub const TupleNamed = extern struct {
+  x: i32,
+  y: f32,
+};
+
+pub extern fn root( a: ?*Opaque,
+                   b: Normal,
+                   c: NormalWithZST,
+                   d: TupleRenamed,
+                   e: TupleNamed) anyopaque;
diff --git a/tests/expectations/struct_literal.zig b/tests/expectations/struct_literal.zig
index 95a0b682a..2cb5b0308 100644
--- a/tests/expectations/struct_literal.zig
+++ b/tests/expectations/struct_literal.zig
@@ -1 +1,24 @@
-const std = @import("std");
+pub const Bar = opaque {};
+pub const Foo = extern struct {
+    a: i32,
+    b: u32,
+};
+
+pub const Foo_FOO = @import("std").mem.zeroInit(Foo, .{
+    .a = @as(c_int, 42),
+    .b = @as(c_int, 47),
+});
+pub const Foo_FOO2 = @import("std").mem.zeroInit(Foo, .{
+    .a = @as(c_int, 42),
+    .b = @as(c_int, 47),
+});
+pub const Foo_FOO3 = @import("std").mem.zeroInit(Foo, .{
+    .a = @as(c_int, 42),
+    .b = @as(c_int, 47),
+});
+pub const BAR = @import("std").mem.zeroInit(Foo, .{
+    .a = @as(c_int, 42),
+    .b = @as(c_int, 1337),
+});
+
+pub extern fn root(x: Foo, bar: Bar) void;
diff --git a/tests/expectations/struct_self.zig b/tests/expectations/struct_self.zig
new file mode 100644
index 000000000..e9e179f30
--- /dev/null
+++ b/tests/expectations/struct_self.zig
@@ -0,0 +1,12 @@
+const std = @import("std");
+
+pub const Foo_Bar = extern struct {
+   something: ?*i32,
+};
+
+pub const Bar = extern struct {
+  something: i32,
+  subexpressions: Foo_Bar,
+};
+
+pub extern fn root(b: Bar) anyopaque;
diff --git a/tests/expectations/swift_name.zig b/tests/expectations/swift_name.zig
index 95a0b682a..24351d4f6 100644
--- a/tests/expectations/swift_name.zig
+++ b/tests/expectations/swift_name.zig
@@ -1 +1,49 @@
 const std = @import("std");
+
+pub const Opaque = opaque {};
+
+pub const SelfTypeTestStruct = extern struct {
+    times: u8,
+};
+
+pub const PointerToOpaque = extern struct {
+    ptr: ?*Opaque,
+};
+
+pub extern fn rust_print_hello_world() anyopaque;
+
+pub extern fn SelfTypeTestStruct_should_exist_ref(self: [*]const SelfTypeTestStruct) anyopaque;
+
+pub extern fn SelfTypeTestStruct_should_exist_ref_mut(self: [*]SelfTypeTestStruct) anyopaque;
+
+pub extern fn SelfTypeTestStruct_should_not_exist_box(self: [*]SelfTypeTestStruct) anyopaque;
+
+pub extern fn SelfTypeTestStruct_should_not_exist_return_box() [*]SelfTypeTestStruct;
+
+pub extern fn SelfTypeTestStruct_should_exist_annotated_self(self: SelfTypeTestStruct) anyopaque;
+
+pub extern fn SelfTypeTestStruct_should_exist_annotated_mut_self(self: SelfTypeTestStruct) anyopaque;
+
+pub extern fn SelfTypeTestStruct_should_exist_annotated_by_name(self: SelfTypeTestStruct) anyopaque;
+
+pub extern fn SelfTypeTestStruct_should_exist_annotated_mut_by_name(self: SelfTypeTestStruct) anyopaque;
+
+pub extern fn SelfTypeTestStruct_should_exist_unannotated(self: SelfTypeTestStruct) anyopaque;
+
+pub extern fn SelfTypeTestStruct_should_exist_mut_unannotated(self: SelfTypeTestStruct) anyopaque;
+
+pub extern fn free_function_should_exist_ref(test_struct: [*]const SelfTypeTestStruct) anyopaque;
+
+pub extern fn free_function_should_exist_ref_mut(test_struct: [*]SelfTypeTestStruct) anyopaque;
+
+pub extern fn unnamed_argument([*]SelfTypeTestStruct) anyopaque;
+
+pub extern fn free_function_should_not_exist_box(boxed: [*]SelfTypeTestStruct) anyopaque;
+
+pub extern fn free_function_should_exist_annotated_by_name(test_struct: SelfTypeTestStruct) anyopaque;
+
+pub extern fn free_function_should_exist_annotated_mut_by_name(test_struct: SelfTypeTestStruct) anyopaque;
+
+pub extern fn PointerToOpaque_create(times: u8) PointerToOpaque;
+
+pub extern fn PointerToOpaque_sayHello(self: PointerToOpaque) anyopaque;
diff --git a/tests/expectations/transform_op.zig b/tests/expectations/transform_op.zig
index 95a0b682a..c99bd318a 100644
--- a/tests/expectations/transform_op.zig
+++ b/tests/expectations/transform_op.zig
@@ -1 +1,93 @@
 const std = @import("std");
+
+pub const Point_i32 = extern struct {
+    x: i32,
+    y: i32,
+};
+
+pub const Point_f32 = extern struct {
+    x: f32,
+    y: f32,
+};
+
+pub const Foo_i32_Tag = enum {
+    Foo_i32,
+    Bar_i32,
+    Baz_i32,
+    Bazz_i32,
+};
+
+pub const Foo_Body_i32 = extern struct {
+    tag: Foo_i32_Tag,
+    x: i32,
+    y: Point_i32,
+    z: Point_f32,
+};
+
+pub const Foo_i32 = extern union {
+    tag: Foo_i32_Tag,
+    foo: Foo_Body_i32,
+};
+
+pub const Bar_i32_Tag = enum {
+    Bar1_i32,
+    Bar2_i32,
+    Bar3_i32,
+    Bar4_i32,
+};
+
+pub const Bar1_Body_i32 = extern struct {
+    x: i32,
+    y: Point_i32,
+    z: Point_f32,
+    u: ?fn () i32,
+};
+
+pub const Bar_i32 = extern struct {
+    tag: Bar_i32_Tag,
+};
+
+pub const Point_u32 = extern struct {
+    x: u32,
+    y: u32,
+};
+
+pub const Bar_u32_Tag = enum {
+    Bar1_u32,
+    Bar2_u32,
+    Bar3_u32,
+    Bar4_u32,
+};
+
+pub const Bar1_Body_u32 = extern struct {
+    x: i32,
+    y: Point_u32,
+    z: Point_f32,
+    u: ?fn () i32,
+};
+
+pub const Bar_u32 = extern struct {
+    tag: Bar_u32_Tag,
+};
+
+pub const Baz_Tag = enum {
+    Baz1,
+    Baz2,
+    Baz3,
+};
+
+pub const Baz = extern union {
+    tag: Baz_Tag,
+};
+
+pub const Taz_Tag = enum {
+    Taz1,
+    Taz2,
+    Taz3,
+};
+
+pub const Taz = extern struct {
+    tag: Taz_Tag,
+};
+
+pub extern fn foo(foo: ?*Foo_i32, bar: ?*Bar_i32, baz: ?*Baz, taz: ?*Taz) anyopaque;
diff --git a/tests/expectations/union.zig b/tests/expectations/union.zig
index 95a0b682a..4f251c11e 100644
--- a/tests/expectations/union.zig
+++ b/tests/expectations/union.zig
@@ -1 +1,15 @@
 const std = @import("std");
+
+const Opaque = opaque {};
+
+pub const Normal = extern union {
+    x: i32,
+    y: f32,
+};
+
+pub const NormalWithZST = extern union {
+    x: i32,
+    y: f32,
+};
+
+pub extern fn root(a: ?*Opaque, b: Normal, c: NormalWithZST) anyopaque;
diff --git a/tests/expectations/union_self.zig b/tests/expectations/union_self.zig
new file mode 100644
index 000000000..8b85870b7
--- /dev/null
+++ b/tests/expectations/union_self.zig
@@ -0,0 +1,12 @@
+const std = @import("std");
+
+pub const Foo_Bar = extern struct {
+    something: ?*i32,
+};
+
+pub const Bar = extern union {
+    something: i32,
+    subexpressions: Foo_Bar,
+};
+
+pub extern fn root(b: Bar) anyopaque;
diff --git a/tests/expectations/using_namespaces.zig b/tests/expectations/using_namespaces.zig
new file mode 100644
index 000000000..d4c2e15c7
--- /dev/null
+++ b/tests/expectations/using_namespaces.zig
@@ -0,0 +1,3 @@
+const std = @import("std");
+
+pub extern fn root() anyopaque;
diff --git a/tests/expectations/va_list.zig b/tests/expectations/va_list.zig
index 95a0b682a..9e7a71bf8 100644
--- a/tests/expectations/va_list.zig
+++ b/tests/expectations/va_list.zig
@@ -1 +1,3 @@
 const std = @import("std");
+
+pub extern fn va_list_test(ap: ...) i32;
diff --git a/tests/expectations/workspace.zig b/tests/expectations/workspace.zig
index 95a0b682a..72f50096d 100644
--- a/tests/expectations/workspace.zig
+++ b/tests/expectations/workspace.zig
@@ -1 +1,7 @@
 const std = @import("std");
+
+pub const ExtType = extern struct {
+    data: u32,
+};
+
+pub extern fn consume_ext(_ext: ExtType) anyopaque;