Fix test breakage after rust-lang/rust#72121

See rust-lang/rust#72121.

The PR fixes some hygiene issues and thus exposes that the originating
expression comes from macros.

Author: Xanewok

tests/cases/pathologic_paths/stdout

@@ -1,19 +1,32 @@
 version bump: 1.0.0 -> (technically breaking) -> 1.1.0
 warning: path changes to `a`
- --> pathologic_paths/new.rs:5:9
-  |
-5 |         pub mod a { blow!($($rest)*); }
-  |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-  |
-  = note: added definition (technically breaking)
+  --> pathologic_paths/new.rs:10:1
+   |
+10 | / blow!(_ _ _ _ _ _ _ _
+11 | |       _ _ _ _ _ _ _ _
+12 | |       _ _ _ _ _ _ _ _
+13 | |       _ _ _ _ _ _ _ _
+...  |
+16 | |       _ _ _ _ _ _ _ _
+17 | |       _ _ _ _ _ _ _ _);
+   | |_______________________^
+   |
+   = note: added definition (technically breaking)
+   = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
 
 warning: path changes to `b`
- --> pathologic_paths/new.rs:6:9
-  |
-6 |         pub mod b { pub use super::a::*; }
-  |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-  |
-  = note: added definition (technically breaking)
-
-warning: 2 warnings emitted
+  --> pathologic_paths/new.rs:10:1
+   |
+10 | / blow!(_ _ _ _ _ _ _ _
+11 | |       _ _ _ _ _ _ _ _
+12 | |       _ _ _ _ _ _ _ _
+13 | |       _ _ _ _ _ _ _ _
+...  |
+16 | |       _ _ _ _ _ _ _ _
+17 | |       _ _ _ _ _ _ _ _);
+   | |_______________________^
+   |
+   = note: added definition (technically breaking)
+   = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
 
+warning: 2 warnings emitted

tests/full_cases/log-0.3.4-0.3.8.linux

@@ -6,6 +6,7 @@ warning: technically breaking changes in `<new::LogLevel as std::hash::Hash>`
     |                           ^^^^
     |
     = note: trait impl generalized or newly added (technically breaking)
+    = note: this warning originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
 
 warning: technically breaking changes in `<new::LogLevelFilter as std::hash::Hash>`
    --> log-0.3.8/src/lib.rs:410:27
@@ -14,6 +15,7 @@ warning: technically breaking changes in `<new::LogLevelFilter as std::hash::Has
     |                           ^^^^
     |
     = note: trait impl generalized or newly added (technically breaking)
+    = note: this warning originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
 
 warning: technically breaking changes in `<new::LogRecord<'a> as std::fmt::Debug>`
    --> log-0.3.8/src/lib.rs:517:10
@@ -22,6 +24,7 @@ warning: technically breaking changes in `<new::LogRecord<'a> as std::fmt::Debug
     |          ^^^^^
     |
     = note: trait impl generalized or newly added (technically breaking)
+    = note: this warning originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
 
 warning: technically breaking changes in `<new::LogMetadata<'a> as std::cmp::Eq>`
    --> log-0.3.8/src/lib.rs:552:10
@@ -30,6 +33,7 @@ warning: technically breaking changes in `<new::LogMetadata<'a> as std::cmp::Eq>
     |          ^^
     |
     = note: trait impl generalized or newly added (technically breaking)
+    = note: this warning originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
 
 warning: technically breaking changes in `<new::LogMetadata<'a> as std::cmp::PartialEq>`
    --> log-0.3.8/src/lib.rs:552:14
@@ -38,6 +42,7 @@ warning: technically breaking changes in `<new::LogMetadata<'a> as std::cmp::Par
     |              ^^^^^^^^^
     |
     = note: trait impl generalized or newly added (technically breaking)
+    = note: this warning originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
 
 warning: technically breaking changes in `<new::LogMetadata<'a> as std::cmp::Ord>`
    --> log-0.3.8/src/lib.rs:552:25
@@ -46,6 +51,7 @@ warning: technically breaking changes in `<new::LogMetadata<'a> as std::cmp::Ord
     |                         ^^^
     |
     = note: trait impl generalized or newly added (technically breaking)
+    = note: this warning originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
 
 warning: technically breaking changes in `<new::LogMetadata<'a> as std::cmp::PartialOrd>`
    --> log-0.3.8/src/lib.rs:552:30
@@ -54,6 +60,7 @@ warning: technically breaking changes in `<new::LogMetadata<'a> as std::cmp::Par
     |                              ^^^^^^^^^^
     |
     = note: trait impl generalized or newly added (technically breaking)
+    = note: this warning originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
 
 warning: technically breaking changes in `<new::LogMetadata<'a> as std::hash::Hash>`
    --> log-0.3.8/src/lib.rs:552:42
@@ -62,6 +69,7 @@ warning: technically breaking changes in `<new::LogMetadata<'a> as std::hash::Ha
     |                                          ^^^^
     |
     = note: trait impl generalized or newly added (technically breaking)
+    = note: this warning originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
 
 warning: technically breaking changes in `<new::LogMetadata<'a> as std::fmt::Debug>`
    --> log-0.3.8/src/lib.rs:552:48
@@ -70,6 +78,7 @@ warning: technically breaking changes in `<new::LogMetadata<'a> as std::fmt::Deb
     |                                                ^^^^^
     |
     = note: trait impl generalized or newly added (technically breaking)
+    = note: this warning originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
 
 warning: technically breaking changes in `<new::LogLocation as std::cmp::Eq>`
    --> log-0.3.8/src/lib.rs:604:30
@@ -78,6 +87,7 @@ warning: technically breaking changes in `<new::LogLocation as std::cmp::Eq>`
     |                              ^^
     |
     = note: trait impl generalized or newly added (technically breaking)
+    = note: this warning originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
 
 warning: technically breaking changes in `<new::LogLocation as std::cmp::PartialEq>`
    --> log-0.3.8/src/lib.rs:604:34
@@ -86,6 +96,7 @@ warning: technically breaking changes in `<new::LogLocation as std::cmp::Partial
     |                                  ^^^^^^^^^
     |
     = note: trait impl generalized or newly added (technically breaking)
+    = note: this warning originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
 
 warning: technically breaking changes in `<new::LogLocation as std::cmp::Ord>`
    --> log-0.3.8/src/lib.rs:604:45
@@ -94,6 +105,7 @@ warning: technically breaking changes in `<new::LogLocation as std::cmp::Ord>`
     |                                             ^^^
     |
     = note: trait impl generalized or newly added (technically breaking)
+    = note: this warning originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
 
 warning: technically breaking changes in `<new::LogLocation as std::cmp::PartialOrd>`
    --> log-0.3.8/src/lib.rs:604:50
@@ -102,6 +114,7 @@ warning: technically breaking changes in `<new::LogLocation as std::cmp::Partial
     |                                                  ^^^^^^^^^^
     |
     = note: trait impl generalized or newly added (technically breaking)
+    = note: this warning originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
 
 warning: technically breaking changes in `<new::LogLocation as std::hash::Hash>`
    --> log-0.3.8/src/lib.rs:604:62
@@ -110,6 +123,7 @@ warning: technically breaking changes in `<new::LogLocation as std::hash::Hash>`
     |                                                              ^^^^
     |
     = note: trait impl generalized or newly added (technically breaking)
+    = note: this warning originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
 
 warning: path changes to `set_logger_raw`
    --> log-0.3.8/src/lib.rs:713:1