Improve namespace handling in imports. (#4153)

This implements a few closely related features:

- Starts merging namespaces discovered inside imports.
- Stores results of cross-package name lookup as an entry inside the
scope.
  - Note this is particularly visible with `i32`.
- Moves more of the imported instructions to the import scope.

Note this is primarily for executing the namespace TODO in check.cpp,
which is removed here.
`testdata/namespace/merging_with_indirections.carbon` tests key
behavior.

---------

Co-authored-by: Richard Smith <richard@metafoo.co.uk>

toolchain/check/testdata/array/array_in_place.carbon

@@ -36,22 +36,8 @@ fn G() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.2: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.3: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.4: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.5: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.6: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
-// CHECK:STDOUT: file {
-// CHECK:STDOUT:   package: <namespace> = namespace [template] {
-// CHECK:STDOUT:     .Core = %Core
-// CHECK:STDOUT:     .F = %F.decl
-// CHECK:STDOUT:     .G = %G.decl
-// CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
+// CHECK:STDOUT:     .Int32 = %import_ref
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -60,6 +46,16 @@ fn G() {
 // CHECK:STDOUT:     import Core//prelude/operators/comparison
 // CHECK:STDOUT:     import Core//prelude/types/bool
 // CHECK:STDOUT:   }
+// CHECK:STDOUT:   %import_ref: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: file {
+// CHECK:STDOUT:   package: <namespace> = namespace [template] {
+// CHECK:STDOUT:     .Core = imports.%Core
+// CHECK:STDOUT:     .F = %F.decl
+// CHECK:STDOUT:     .G = %G.decl
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %F.decl: %F.type = fn_decl @F [template = constants.%F] {
 // CHECK:STDOUT:     %int.make_type_32.loc11_12: init type = call constants.%Int32() [template = i32]
 // CHECK:STDOUT:     %int.make_type_32.loc11_17: init type = call constants.%Int32() [template = i32]

toolchain/check/testdata/array/array_vs_tuple.carbon

@@ -36,19 +36,8 @@ fn G() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.2: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.3: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.4: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
-// CHECK:STDOUT: file {
-// CHECK:STDOUT:   package: <namespace> = namespace [template] {
-// CHECK:STDOUT:     .Core = %Core
-// CHECK:STDOUT:     .G = %G.decl
-// CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
+// CHECK:STDOUT:     .Int32 = %import_ref
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -57,6 +46,15 @@ fn G() {
 // CHECK:STDOUT:     import Core//prelude/operators/comparison
 // CHECK:STDOUT:     import Core//prelude/types/bool
 // CHECK:STDOUT:   }
+// CHECK:STDOUT:   %import_ref: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: file {
+// CHECK:STDOUT:   package: <namespace> = namespace [template] {
+// CHECK:STDOUT:     .Core = imports.%Core
+// CHECK:STDOUT:     .G = %G.decl
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %G.decl: %G.type = fn_decl @G [template = constants.%G] {}
 // CHECK:STDOUT: }
 // CHECK:STDOUT:

toolchain/check/testdata/array/assign_return_value.carbon

@@ -34,18 +34,8 @@ fn Run() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.2: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
-// CHECK:STDOUT: file {
-// CHECK:STDOUT:   package: <namespace> = namespace [template] {
-// CHECK:STDOUT:     .Core = %Core
-// CHECK:STDOUT:     .F = %F.decl
-// CHECK:STDOUT:     .Run = %Run.decl
-// CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
+// CHECK:STDOUT:     .Int32 = %import_ref
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -54,6 +44,16 @@ fn Run() {
 // CHECK:STDOUT:     import Core//prelude/operators/comparison
 // CHECK:STDOUT:     import Core//prelude/types/bool
 // CHECK:STDOUT:   }
+// CHECK:STDOUT:   %import_ref: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: file {
+// CHECK:STDOUT:   package: <namespace> = namespace [template] {
+// CHECK:STDOUT:     .Core = imports.%Core
+// CHECK:STDOUT:     .F = %F.decl
+// CHECK:STDOUT:     .Run = %Run.decl
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %F.decl: %F.type = fn_decl @F [template = constants.%F] {
 // CHECK:STDOUT:     %int.make_type_32: init type = call constants.%Int32() [template = i32]
 // CHECK:STDOUT:     %.loc11_16.1: %.2 = tuple_literal (%int.make_type_32)

toolchain/check/testdata/array/assign_var.carbon

@@ -30,20 +30,8 @@ var b: [i32; 3] = a;
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.2: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.3: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.4: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
-// CHECK:STDOUT: file {
-// CHECK:STDOUT:   package: <namespace> = namespace [template] {
-// CHECK:STDOUT:     .Core = %Core
-// CHECK:STDOUT:     .a = %a
-// CHECK:STDOUT:     .b = %b
-// CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
+// CHECK:STDOUT:     .Int32 = %import_ref
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -52,6 +40,16 @@ var b: [i32; 3] = a;
 // CHECK:STDOUT:     import Core//prelude/operators/comparison
 // CHECK:STDOUT:     import Core//prelude/types/bool
 // CHECK:STDOUT:   }
+// CHECK:STDOUT:   %import_ref: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: file {
+// CHECK:STDOUT:   package: <namespace> = namespace [template] {
+// CHECK:STDOUT:     .Core = imports.%Core
+// CHECK:STDOUT:     .a = %a
+// CHECK:STDOUT:     .b = %b
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %int.make_type_32.loc11_9: init type = call constants.%Int32() [template = i32]
 // CHECK:STDOUT:   %int.make_type_32.loc11_14: init type = call constants.%Int32() [template = i32]
 // CHECK:STDOUT:   %int.make_type_32.loc11_19: init type = call constants.%Int32() [template = i32]

toolchain/check/testdata/array/base.carbon

@@ -45,19 +45,9 @@ var c: [(); 5] = ((), (), (), (), (),);
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.2: %Float.type = import_ref Core//prelude/types, inst+32, loaded [template = constants.%Float]
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
-// CHECK:STDOUT: file {
-// CHECK:STDOUT:   package: <namespace> = namespace [template] {
-// CHECK:STDOUT:     .Core = %Core
-// CHECK:STDOUT:     .a = %a
-// CHECK:STDOUT:     .b = %b
-// CHECK:STDOUT:     .c = %c
-// CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
+// CHECK:STDOUT:     .Int32 = %import_ref.1
+// CHECK:STDOUT:     .Float = %import_ref.2
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -66,6 +56,18 @@ var c: [(); 5] = ((), (), (), (), (),);
 // CHECK:STDOUT:     import Core//prelude/operators/comparison
 // CHECK:STDOUT:     import Core//prelude/types/bool
 // CHECK:STDOUT:   }
+// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.2: %Float.type = import_ref Core//prelude/types, inst+32, loaded [template = constants.%Float]
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: file {
+// CHECK:STDOUT:   package: <namespace> = namespace [template] {
+// CHECK:STDOUT:     .Core = imports.%Core
+// CHECK:STDOUT:     .a = %a
+// CHECK:STDOUT:     .b = %b
+// CHECK:STDOUT:     .c = %c
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %int.make_type_32: init type = call constants.%Int32() [template = i32]
 // CHECK:STDOUT:   %.loc11_14: i32 = int_literal 1 [template = constants.%.2]
 // CHECK:STDOUT:   %.loc11_9.1: type = value_of_initializer %int.make_type_32 [template = i32]

toolchain/check/testdata/array/canonicalize_index.carbon

@@ -32,22 +32,8 @@ let b: [i32; 3]* = &a;
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.2: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.3: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.4: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.5: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
-// CHECK:STDOUT: file {
-// CHECK:STDOUT:   package: <namespace> = namespace [template] {
-// CHECK:STDOUT:     .Core = %Core
-// CHECK:STDOUT:     .Add = %Add.decl
-// CHECK:STDOUT:     .a = %a.loc13
-// CHECK:STDOUT:     .b = @__global_init.%b
-// CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
+// CHECK:STDOUT:     .Int32 = %import_ref
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -56,6 +42,17 @@ let b: [i32; 3]* = &a;
 // CHECK:STDOUT:     import Core//prelude/operators/comparison
 // CHECK:STDOUT:     import Core//prelude/types/bool
 // CHECK:STDOUT:   }
+// CHECK:STDOUT:   %import_ref: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: file {
+// CHECK:STDOUT:   package: <namespace> = namespace [template] {
+// CHECK:STDOUT:     .Core = imports.%Core
+// CHECK:STDOUT:     .Add = %Add.decl
+// CHECK:STDOUT:     .a = %a.loc13
+// CHECK:STDOUT:     .b = @__global_init.%b
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %Add.decl: %Add.type = fn_decl @Add [template = constants.%Add] {
 // CHECK:STDOUT:     %int.make_type_32.loc11_11: init type = call constants.%Int32() [template = i32]
 // CHECK:STDOUT:     %.loc11_11.1: type = value_of_initializer %int.make_type_32.loc11_11 [template = i32]

toolchain/check/testdata/array/fail_bound_negative.carbon

@@ -28,19 +28,8 @@ var a: [i32; Negate(1)];
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.2: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.3: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
-// CHECK:STDOUT: file {
-// CHECK:STDOUT:   package: <namespace> = namespace [template] {
-// CHECK:STDOUT:     .Core = %Core
-// CHECK:STDOUT:     .Negate = %Negate.decl
-// CHECK:STDOUT:     .a = %a
-// CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
+// CHECK:STDOUT:     .Int32 = %import_ref
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -49,6 +38,16 @@ var a: [i32; Negate(1)];
 // CHECK:STDOUT:     import Core//prelude/operators/comparison
 // CHECK:STDOUT:     import Core//prelude/types/bool
 // CHECK:STDOUT:   }
+// CHECK:STDOUT:   %import_ref: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: file {
+// CHECK:STDOUT:   package: <namespace> = namespace [template] {
+// CHECK:STDOUT:     .Core = imports.%Core
+// CHECK:STDOUT:     .Negate = %Negate.decl
+// CHECK:STDOUT:     .a = %a
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %Negate.decl: %Negate.type = fn_decl @Negate [template = constants.%Negate] {
 // CHECK:STDOUT:     %int.make_type_32.loc11_14: init type = call constants.%Int32() [template = i32]
 // CHECK:STDOUT:     %.loc11_14.1: type = value_of_initializer %int.make_type_32.loc11_14 [template = i32]

toolchain/check/testdata/array/fail_bound_overflow.carbon

@@ -36,17 +36,8 @@ var b: [1; 39999999999999999993];
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
-// CHECK:STDOUT: file {
-// CHECK:STDOUT:   package: <namespace> = namespace [template] {
-// CHECK:STDOUT:     .Core = %Core
-// CHECK:STDOUT:     .a = %a
-// CHECK:STDOUT:     .b = %b
-// CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
+// CHECK:STDOUT:     .Int32 = %import_ref
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -55,6 +46,16 @@ var b: [1; 39999999999999999993];
 // CHECK:STDOUT:     import Core//prelude/operators/comparison
 // CHECK:STDOUT:     import Core//prelude/types/bool
 // CHECK:STDOUT:   }
+// CHECK:STDOUT:   %import_ref: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: file {
+// CHECK:STDOUT:   package: <namespace> = namespace [template] {
+// CHECK:STDOUT:     .Core = imports.%Core
+// CHECK:STDOUT:     .a = %a
+// CHECK:STDOUT:     .b = %b
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %int.make_type_32: init type = call constants.%Int32() [template = i32]
 // CHECK:STDOUT:   %.loc18_9.1: type = value_of_initializer %int.make_type_32 [template = i32]
 // CHECK:STDOUT:   %.loc18_9.2: type = converted %int.make_type_32, %.loc18_9.1 [template = i32]

toolchain/check/testdata/array/fail_incomplete_element.carbon

@@ -30,15 +30,8 @@ var p: Incomplete* = &a[0];
 // CHECK:STDOUT:   %.4: i32 = int_literal 0 [template]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
-// CHECK:STDOUT: file {
-// CHECK:STDOUT:   package: <namespace> = namespace [template] {
-// CHECK:STDOUT:     .Core = %Core
-// CHECK:STDOUT:     .Incomplete = %Incomplete.decl
-// CHECK:STDOUT:     .a = %a
-// CHECK:STDOUT:     .p = %p
-// CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT: imports {
+// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -47,6 +40,16 @@ var p: Incomplete* = &a[0];
 // CHECK:STDOUT:     import Core//prelude/operators/comparison
 // CHECK:STDOUT:     import Core//prelude/types/bool
 // CHECK:STDOUT:   }
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: file {
+// CHECK:STDOUT:   package: <namespace> = namespace [template] {
+// CHECK:STDOUT:     .Core = imports.%Core
+// CHECK:STDOUT:     .Incomplete = %Incomplete.decl
+// CHECK:STDOUT:     .a = %a
+// CHECK:STDOUT:     .p = %p
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %Incomplete.decl: type = class_decl @Incomplete [template = constants.%Incomplete] {}
 // CHECK:STDOUT:   %Incomplete.ref.loc19: type = name_ref Incomplete, %Incomplete.decl [template = constants.%Incomplete]
 // CHECK:STDOUT:   %.loc19_21: i32 = int_literal 1 [template = constants.%.1]

toolchain/check/testdata/array/fail_invalid_type.carbon

@@ -19,13 +19,8 @@ var a: [1; 1];
 // CHECK:STDOUT:   %.1: i32 = int_literal 1 [template]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
-// CHECK:STDOUT: file {
-// CHECK:STDOUT:   package: <namespace> = namespace [template] {
-// CHECK:STDOUT:     .Core = %Core
-// CHECK:STDOUT:     .a = %a
-// CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT: imports {
+// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -34,6 +29,14 @@ var a: [1; 1];
 // CHECK:STDOUT:     import Core//prelude/operators/comparison
 // CHECK:STDOUT:     import Core//prelude/types/bool
 // CHECK:STDOUT:   }
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: file {
+// CHECK:STDOUT:   package: <namespace> = namespace [template] {
+// CHECK:STDOUT:     .Core = imports.%Core
+// CHECK:STDOUT:     .a = %a
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %.loc14_9: i32 = int_literal 1 [template = constants.%.1]
 // CHECK:STDOUT:   %.loc14_12: i32 = int_literal 1 [template = constants.%.1]
 // CHECK:STDOUT:   %.loc14_13: type = array_type %.loc14_12, <error> [template = <error>]

toolchain/check/testdata/array/fail_out_of_bound.carbon

@@ -28,16 +28,8 @@ var a: [i32; 1] = (1, 2, 3);
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
-// CHECK:STDOUT: file {
-// CHECK:STDOUT:   package: <namespace> = namespace [template] {
-// CHECK:STDOUT:     .Core = %Core
-// CHECK:STDOUT:     .a = %a
-// CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
+// CHECK:STDOUT:     .Int32 = %import_ref
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -46,6 +38,15 @@ var a: [i32; 1] = (1, 2, 3);
 // CHECK:STDOUT:     import Core//prelude/operators/comparison
 // CHECK:STDOUT:     import Core//prelude/types/bool
 // CHECK:STDOUT:   }
+// CHECK:STDOUT:   %import_ref: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: file {
+// CHECK:STDOUT:   package: <namespace> = namespace [template] {
+// CHECK:STDOUT:     .Core = imports.%Core
+// CHECK:STDOUT:     .a = %a
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %int.make_type_32: init type = call constants.%Int32() [template = i32]
 // CHECK:STDOUT:   %.loc14_14: i32 = int_literal 1 [template = constants.%.2]
 // CHECK:STDOUT:   %.loc14_9.1: type = value_of_initializer %int.make_type_32 [template = i32]

toolchain/check/testdata/array/fail_out_of_bound_non_literal.carbon

@@ -33,18 +33,8 @@ var b: i32 = a[{.index = 3}.index];
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.2: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
-// CHECK:STDOUT: file {
-// CHECK:STDOUT:   package: <namespace> = namespace [template] {
-// CHECK:STDOUT:     .Core = %Core
-// CHECK:STDOUT:     .a = %a
-// CHECK:STDOUT:     .b = %b
-// CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
+// CHECK:STDOUT:     .Int32 = %import_ref
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -53,6 +43,16 @@ var b: i32 = a[{.index = 3}.index];
 // CHECK:STDOUT:     import Core//prelude/operators/comparison
 // CHECK:STDOUT:     import Core//prelude/types/bool
 // CHECK:STDOUT:   }
+// CHECK:STDOUT:   %import_ref: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: file {
+// CHECK:STDOUT:   package: <namespace> = namespace [template] {
+// CHECK:STDOUT:     .Core = imports.%Core
+// CHECK:STDOUT:     .a = %a
+// CHECK:STDOUT:     .b = %b
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %int.make_type_32.loc11: init type = call constants.%Int32() [template = i32]
 // CHECK:STDOUT:   %.loc11_14: i32 = int_literal 3 [template = constants.%.2]
 // CHECK:STDOUT:   %.loc11_9.1: type = value_of_initializer %int.make_type_32.loc11 [template = i32]

toolchain/check/testdata/array/fail_type_mismatch.carbon

@@ -58,27 +58,8 @@ var d: [i32; 3] = t2;
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.2: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.3: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.4: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.5: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.6: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.7: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
-// CHECK:STDOUT: file {
-// CHECK:STDOUT:   package: <namespace> = namespace [template] {
-// CHECK:STDOUT:     .Core = %Core
-// CHECK:STDOUT:     .a = %a
-// CHECK:STDOUT:     .t1 = %t1
-// CHECK:STDOUT:     .b = %b
-// CHECK:STDOUT:     .c = %c
-// CHECK:STDOUT:     .t2 = %t2
-// CHECK:STDOUT:     .d = %d
-// CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
+// CHECK:STDOUT:     .Int32 = %import_ref
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -87,6 +68,20 @@ var d: [i32; 3] = t2;
 // CHECK:STDOUT:     import Core//prelude/operators/comparison
 // CHECK:STDOUT:     import Core//prelude/types/bool
 // CHECK:STDOUT:   }
+// CHECK:STDOUT:   %import_ref: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: file {
+// CHECK:STDOUT:   package: <namespace> = namespace [template] {
+// CHECK:STDOUT:     .Core = imports.%Core
+// CHECK:STDOUT:     .a = %a
+// CHECK:STDOUT:     .t1 = %t1
+// CHECK:STDOUT:     .b = %b
+// CHECK:STDOUT:     .c = %c
+// CHECK:STDOUT:     .t2 = %t2
+// CHECK:STDOUT:     .d = %d
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %int.make_type_32.loc15: init type = call constants.%Int32() [template = i32]
 // CHECK:STDOUT:   %.loc15_14: i32 = int_literal 3 [template = constants.%.2]
 // CHECK:STDOUT:   %.loc15_9.1: type = value_of_initializer %int.make_type_32.loc15 [template = i32]

toolchain/check/testdata/array/function_param.carbon

@@ -37,20 +37,8 @@ fn G() -> i32 {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.2: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.3: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.4: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
-// CHECK:STDOUT: file {
-// CHECK:STDOUT:   package: <namespace> = namespace [template] {
-// CHECK:STDOUT:     .Core = %Core
-// CHECK:STDOUT:     .F = %F.decl
-// CHECK:STDOUT:     .G = %G.decl
-// CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
+// CHECK:STDOUT:     .Int32 = %import_ref
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -59,6 +47,16 @@ fn G() -> i32 {
 // CHECK:STDOUT:     import Core//prelude/operators/comparison
 // CHECK:STDOUT:     import Core//prelude/types/bool
 // CHECK:STDOUT:   }
+// CHECK:STDOUT:   %import_ref: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: file {
+// CHECK:STDOUT:   package: <namespace> = namespace [template] {
+// CHECK:STDOUT:     .Core = imports.%Core
+// CHECK:STDOUT:     .F = %F.decl
+// CHECK:STDOUT:     .G = %G.decl
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %F.decl: %F.type = fn_decl @F [template = constants.%F] {
 // CHECK:STDOUT:     %int.make_type_32.loc11_12: init type = call constants.%Int32() [template = i32]
 // CHECK:STDOUT:     %.loc11_17: i32 = int_literal 3 [template = constants.%.2]

toolchain/check/testdata/array/generic_empty.carbon

@@ -26,13 +26,8 @@ fn G(T:! type) {
 // CHECK:STDOUT:   %array: %.3 = tuple_value () [symbolic]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
-// CHECK:STDOUT: file {
-// CHECK:STDOUT:   package: <namespace> = namespace [template] {
-// CHECK:STDOUT:     .Core = %Core
-// CHECK:STDOUT:     .G = %G.decl
-// CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT: imports {
+// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -41,6 +36,14 @@ fn G(T:! type) {
 // CHECK:STDOUT:     import Core//prelude/operators/comparison
 // CHECK:STDOUT:     import Core//prelude/types/bool
 // CHECK:STDOUT:   }
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: file {
+// CHECK:STDOUT:   package: <namespace> = namespace [template] {
+// CHECK:STDOUT:     .Core = imports.%Core
+// CHECK:STDOUT:     .G = %G.decl
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %G.decl: %G.type = fn_decl @G [template = constants.%G] {
 // CHECK:STDOUT:     %T.loc11_6.1: type = param T
 // CHECK:STDOUT:     @G.%T.loc11: type = bind_symbolic_name T 0, %T.loc11_6.1 [symbolic = @G.%T.1 (constants.%T)]

toolchain/check/testdata/array/index_not_literal.carbon

@@ -30,18 +30,8 @@ var b: i32 = a[{.index = 2}.index];
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.2: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
-// CHECK:STDOUT: file {
-// CHECK:STDOUT:   package: <namespace> = namespace [template] {
-// CHECK:STDOUT:     .Core = %Core
-// CHECK:STDOUT:     .a = %a
-// CHECK:STDOUT:     .b = %b
-// CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
+// CHECK:STDOUT:     .Int32 = %import_ref
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -50,6 +40,16 @@ var b: i32 = a[{.index = 2}.index];
 // CHECK:STDOUT:     import Core//prelude/operators/comparison
 // CHECK:STDOUT:     import Core//prelude/types/bool
 // CHECK:STDOUT:   }
+// CHECK:STDOUT:   %import_ref: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: file {
+// CHECK:STDOUT:   package: <namespace> = namespace [template] {
+// CHECK:STDOUT:     .Core = imports.%Core
+// CHECK:STDOUT:     .a = %a
+// CHECK:STDOUT:     .b = %b
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %int.make_type_32.loc11: init type = call constants.%Int32() [template = i32]
 // CHECK:STDOUT:   %.loc11_14: i32 = int_literal 3 [template = constants.%.2]
 // CHECK:STDOUT:   %.loc11_9.1: type = value_of_initializer %int.make_type_32.loc11 [template = i32]

toolchain/check/testdata/array/nine_elements.carbon

@@ -33,16 +33,8 @@ var a: [i32; 9] = (1, 2, 3, 4, 5, 6, 7, 8, 9);
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
-// CHECK:STDOUT: file {
-// CHECK:STDOUT:   package: <namespace> = namespace [template] {
-// CHECK:STDOUT:     .Core = %Core
-// CHECK:STDOUT:     .a = %a
-// CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
+// CHECK:STDOUT:     .Int32 = %import_ref
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -51,6 +43,15 @@ var a: [i32; 9] = (1, 2, 3, 4, 5, 6, 7, 8, 9);
 // CHECK:STDOUT:     import Core//prelude/operators/comparison
 // CHECK:STDOUT:     import Core//prelude/types/bool
 // CHECK:STDOUT:   }
+// CHECK:STDOUT:   %import_ref: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: file {
+// CHECK:STDOUT:   package: <namespace> = namespace [template] {
+// CHECK:STDOUT:     .Core = imports.%Core
+// CHECK:STDOUT:     .a = %a
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %int.make_type_32: init type = call constants.%Int32() [template = i32]
 // CHECK:STDOUT:   %.loc11_14: i32 = int_literal 9 [template = constants.%.2]
 // CHECK:STDOUT:   %.loc11_9.1: type = value_of_initializer %int.make_type_32 [template = i32]