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/if_expr/basic.carbon

@@ -32,20 +32,9 @@ fn F(b: bool, n: i32, m: i32) -> i32 {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %Bool.type = import_ref Core//prelude/types/bool, inst+2, loaded [template = constants.%Bool]
-// 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:     .F = %F.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:     .Bool = %import_ref.1
+// CHECK:STDOUT:     .Int32 = %import_ref.2
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -54,6 +43,16 @@ fn F(b: bool, n: i32, m: i32) -> i32 {
 // CHECK:STDOUT:     import Core//prelude/operators/comparison
 // CHECK:STDOUT:     import Core//prelude/types/bool
 // CHECK:STDOUT:   }
+// CHECK:STDOUT:   %import_ref.1: %Bool.type = import_ref Core//prelude/types/bool, inst+2, loaded [template = constants.%Bool]
+// 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 = imports.%Core
+// CHECK:STDOUT:     .F = %F.decl
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %F.decl: %F.type = fn_decl @F [template = constants.%F] {
 // CHECK:STDOUT:     %bool.make_type: init type = call constants.%Bool() [template = bool]
 // CHECK:STDOUT:     %.loc11_9.1: type = value_of_initializer %bool.make_type [template = bool]

toolchain/check/testdata/if_expr/constant_condition.carbon

@@ -57,32 +57,8 @@ fn PartiallyConstant(t: type) -> 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:   %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:   %import_ref.8: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.9: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.10: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.11: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.12: %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.decl
-// CHECK:STDOUT:     .B = %B.decl
-// CHECK:STDOUT:     .F = %F.decl
-// CHECK:STDOUT:     .G = %G.decl
-// CHECK:STDOUT:     .Constant = %Constant.decl
-// CHECK:STDOUT:     .PartiallyConstant = %PartiallyConstant.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
@@ -91,6 +67,20 @@ fn PartiallyConstant(t: type) -> 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:     .A = %A.decl
+// CHECK:STDOUT:     .B = %B.decl
+// CHECK:STDOUT:     .F = %F.decl
+// CHECK:STDOUT:     .G = %G.decl
+// CHECK:STDOUT:     .Constant = %Constant.decl
+// CHECK:STDOUT:     .PartiallyConstant = %PartiallyConstant.decl
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %A.decl: %A.type = fn_decl @A [template = constants.%A] {
 // CHECK:STDOUT:     %int.make_type_32.loc11: init type = call constants.%Int32() [template = i32]
 // CHECK:STDOUT:     %.loc11_11.1: type = value_of_initializer %int.make_type_32.loc11 [template = i32]

toolchain/check/testdata/if_expr/control_flow.carbon

@@ -34,21 +34,9 @@ fn F(b: bool) -> 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: %Bool.type = import_ref Core//prelude/types/bool, inst+2, loaded [template = constants.%Bool]
-// 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.decl
-// CHECK:STDOUT:     .B = %B.decl
-// CHECK:STDOUT:     .F = %F.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.1
+// CHECK:STDOUT:     .Bool = %import_ref.2
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -57,6 +45,18 @@ fn F(b: bool) -> i32 {
 // 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: %Bool.type = import_ref Core//prelude/types/bool, inst+2, loaded [template = constants.%Bool]
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: file {
+// CHECK:STDOUT:   package: <namespace> = namespace [template] {
+// CHECK:STDOUT:     .Core = imports.%Core
+// CHECK:STDOUT:     .A = %A.decl
+// CHECK:STDOUT:     .B = %B.decl
+// CHECK:STDOUT:     .F = %F.decl
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %A.decl: %A.type = fn_decl @A [template = constants.%A] {
 // CHECK:STDOUT:     %int.make_type_32.loc11: init type = call constants.%Int32() [template = i32]
 // CHECK:STDOUT:     %.loc11_11.1: type = value_of_initializer %int.make_type_32.loc11 [template = i32]

toolchain/check/testdata/if_expr/fail_not_in_function.carbon

@@ -55,19 +55,9 @@ class C {
 // 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: %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:     .x = <unexpected>.inst+12.loc23_5
-// CHECK:STDOUT:     .C = %C.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.1
+// CHECK:STDOUT:     .Float = %import_ref.2
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -76,6 +66,17 @@ class C {
 // 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:     .x = <unexpected>.inst+12.loc23_5
+// CHECK:STDOUT:     .C = %C.decl
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %int.make_type_32: init type = call constants.%Int32() [template = i32]
 // CHECK:STDOUT:   %.loc23_8.1: type = value_of_initializer %int.make_type_32 [template = i32]
 // CHECK:STDOUT:   %.loc23_8.2: type = converted %int.make_type_32, %.loc23_8.1 [template = i32]
@@ -88,7 +89,7 @@ class C {
 // CHECK:STDOUT:
 // CHECK:STDOUT: !members:
 // CHECK:STDOUT:   .Self = constants.%C
-// CHECK:STDOUT:   .n = <unexpected>.inst+49.loc37_8
+// CHECK:STDOUT:   .n = <unexpected>.inst+48.loc37_8
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: fn @Int32() -> type = "int.make_type_32";

toolchain/check/testdata/if_expr/fail_partial_constant.carbon

@@ -53,18 +53,9 @@ fn ChosenBranchIsNonConstant(t: type) {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %Bool.type = import_ref Core//prelude/types/bool, inst+2, loaded [template = constants.%Bool]
-// 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:     .ConditionIsNonConstant = %ConditionIsNonConstant.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:     .Bool = %import_ref.1
+// CHECK:STDOUT:     .Int32 = %import_ref.2
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -73,6 +64,16 @@ fn ChosenBranchIsNonConstant(t: type) {
 // CHECK:STDOUT:     import Core//prelude/operators/comparison
 // CHECK:STDOUT:     import Core//prelude/types/bool
 // CHECK:STDOUT:   }
+// CHECK:STDOUT:   %import_ref.1: %Bool.type = import_ref Core//prelude/types/bool, inst+2, loaded [template = constants.%Bool]
+// 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 = imports.%Core
+// CHECK:STDOUT:     .ConditionIsNonConstant = %ConditionIsNonConstant.decl
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %ConditionIsNonConstant.decl: %ConditionIsNonConstant.type = fn_decl @ConditionIsNonConstant [template = constants.%ConditionIsNonConstant] {
 // CHECK:STDOUT:     %bool.make_type: init type = call constants.%Bool() [template = bool]
 // CHECK:STDOUT:     %.loc4_30.1: type = value_of_initializer %bool.make_type [template = bool]
@@ -126,17 +127,8 @@ fn ChosenBranchIsNonConstant(t: type) {
 // 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:     .ChosenBranchIsNonConstant = %ChosenBranchIsNonConstant.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
@@ -145,6 +137,15 @@ fn ChosenBranchIsNonConstant(t: type) {
 // 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:     .ChosenBranchIsNonConstant = %ChosenBranchIsNonConstant.decl
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %ChosenBranchIsNonConstant.decl: %ChosenBranchIsNonConstant.type = fn_decl @ChosenBranchIsNonConstant [template = constants.%ChosenBranchIsNonConstant] {
 // CHECK:STDOUT:     %t.loc4_30.1: type = param t
 // CHECK:STDOUT:     @ChosenBranchIsNonConstant.%t: type = bind_name t, %t.loc4_30.1

toolchain/check/testdata/if_expr/nested.carbon

@@ -29,19 +29,9 @@ fn F(a: bool, b: bool, c: bool) -> i32 {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %Bool.type = import_ref Core//prelude/types/bool, inst+2, loaded [template = constants.%Bool]
-// CHECK:STDOUT:   %import_ref.2: %Bool.type = import_ref Core//prelude/types/bool, inst+2, loaded [template = constants.%Bool]
-// CHECK:STDOUT:   %import_ref.3: %Bool.type = import_ref Core//prelude/types/bool, inst+2, loaded [template = constants.%Bool]
-// 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:   }
-// 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:     .Bool = %import_ref.1
+// CHECK:STDOUT:     .Int32 = %import_ref.2
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -50,6 +40,16 @@ fn F(a: bool, b: bool, c: bool) -> i32 {
 // CHECK:STDOUT:     import Core//prelude/operators/comparison
 // CHECK:STDOUT:     import Core//prelude/types/bool
 // CHECK:STDOUT:   }
+// CHECK:STDOUT:   %import_ref.1: %Bool.type = import_ref Core//prelude/types/bool, inst+2, loaded [template = constants.%Bool]
+// 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 = imports.%Core
+// CHECK:STDOUT:     .F = %F.decl
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %F.decl: %F.type = fn_decl @F [template = constants.%F] {
 // CHECK:STDOUT:     %bool.make_type.loc11_9: init type = call constants.%Bool() [template = bool]
 // CHECK:STDOUT:     %.loc11_9.1: type = value_of_initializer %bool.make_type.loc11_9 [template = bool]

toolchain/check/testdata/if_expr/struct.carbon

@@ -35,21 +35,9 @@ fn F(cond: bool) {
 // 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: %Bool.type = import_ref Core//prelude/types/bool, inst+2, loaded [template = constants.%Bool]
-// 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:     .G = %G.decl
-// CHECK:STDOUT:     .F = %F.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.1
+// CHECK:STDOUT:     .Bool = %import_ref.2
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
 // CHECK:STDOUT:     import Core//prelude/types
@@ -58,6 +46,17 @@ fn F(cond: bool) {
 // 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: %Bool.type = import_ref Core//prelude/types/bool, inst+2, loaded [template = constants.%Bool]
+// 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:     .F = %F.decl
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %G.decl: %G.type = fn_decl @G [template = constants.%G] {
 // 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]