fix(resolver): Have errors follow rustc's casing convention

Author: epage

src/cargo/core/resolver/dep_cache.rs

@@ -524,7 +524,7 @@ impl RequirementError {
                                 "feature",
                             );
                             ActivateError::Fatal(anyhow::format_err!(
-                                "Package `{}` does not have the feature `{}`{}",
+                                "package `{}` does not have the feature `{}`{}",
                                 summary.package_id(),
                                 feat,
                                 closest
@@ -555,9 +555,11 @@ impl RequirementError {
                             }
                             ActivateError::Fatal(anyhow::format_err!(
                                 "\
-Package `{}` does not have feature `{}`. It has an optional dependency \
-with that name, but that dependency uses the \"dep:\" \
-syntax in the features table, so it does not have an implicit feature with that name.{}",
+package `{}` does not have feature `{}`
+
+help: an optional dependency \
+with that name exists, but the `features` table includes it with the \"dep:\" \
+syntax so it does not have an implicit feature with that name{}",
                                 summary.package_id(),
                                 feat,
                                 suggestion
@@ -571,8 +573,9 @@ syntax in the features table, so it does not have an implicit feature with that
                 } else {
                     match parent {
                         None => ActivateError::Fatal(anyhow::format_err!(
-                            "Package `{}` does not have feature `{}`. It has a required dependency \
-                             with that name, but only optional dependencies can be used as features.",
+                            "package `{}` does not have feature `{}`
+
+help: a depednency with that name exists but it is required dependency and only optional dependencies can be used as features.",
                             summary.package_id(),
                             feat,
                         )),

tests/testsuite/features.rs

@@ -232,7 +232,7 @@ failed to select a version for `bar` which could resolve this conflict
     p.cargo("check --features test")
         .with_status(101)
         .with_stderr_data(str![[r#"
-[ERROR] Package `foo v0.0.1 ([ROOT]/foo)` does not have the feature `test`
+[ERROR] package `foo v0.0.1 ([ROOT]/foo)` does not have the feature `test`
 
 "#]])
         .run();
@@ -448,7 +448,9 @@ fn cli_activates_required_dependency() {
     p.cargo("check --features bar")
         .with_stderr_data(str![[r#"
 [LOCKING] 1 package to latest compatible version
-[ERROR] Package `foo v0.0.1 ([ROOT]/foo)` does not have feature `bar`. It has a required dependency with that name, but only optional dependencies can be used as features.
+[ERROR] package `foo v0.0.1 ([ROOT]/foo)` does not have feature `bar`
+
+[HELP] a depednency with that name exists but it is required dependency and only optional dependencies can be used as features.
 
 "#]])
         .with_status(101)

tests/testsuite/features_namespaced.rs

@@ -419,7 +419,9 @@ regex
 
     p.cargo("run --features lazy_static")
         .with_stderr_data(str![[r#"
-[ERROR] Package `foo v0.1.0 ([ROOT]/foo)` does not have feature `lazy_static`. It has an optional dependency with that name, but that dependency uses the "dep:" syntax in the features table, so it does not have an implicit feature with that name.
+[ERROR] package `foo v0.1.0 ([ROOT]/foo)` does not have feature `lazy_static`
+
+[HELP] an optional dependency with that name exists, but the `features` table includes it with the "dep:" syntax so it does not have an implicit feature with that name
 Dependency `lazy_static` would be enabled by these features:
 	- `regex`
 

tests/testsuite/package_features.rs

@@ -338,7 +338,7 @@ f3f4
     p.cargo("run -p bar --features f1,f2")
         .with_status(101)
         .with_stderr_data(str![[r#"
-[ERROR] Package `foo v0.1.0 ([ROOT]/foo)` does not have the feature `f2`
+[ERROR] package `foo v0.1.0 ([ROOT]/foo)` does not have the feature `f2`
 
 [HELP] a feature with a similar name exists: `f1`
 
@@ -406,7 +406,7 @@ fn feature_default_resolver() {
     p.cargo("check --features testt")
         .with_status(101)
         .with_stderr_data(str![[r#"
-[ERROR] Package `a v0.1.0 ([ROOT]/foo)` does not have the feature `testt`
+[ERROR] package `a v0.1.0 ([ROOT]/foo)` does not have the feature `testt`
 
 [HELP] a feature with a similar name exists: `test`
 
@@ -458,7 +458,9 @@ fn command_line_optional_dep() {
         .with_stderr_data(str![[r#"
 [UPDATING] `dummy-registry` index
 [LOCKING] 1 package to latest compatible version
-[ERROR] Package `a v0.1.0 ([ROOT]/foo)` does not have feature `bar`. It has an optional dependency with that name, but that dependency uses the "dep:" syntax in the features table, so it does not have an implicit feature with that name.
+[ERROR] package `a v0.1.0 ([ROOT]/foo)` does not have feature `bar`
+
+[HELP] an optional dependency with that name exists, but the `features` table includes it with the "dep:" syntax so it does not have an implicit feature with that name
 Dependency `bar` would be enabled by these features:
 	- `foo`
 
@@ -496,7 +498,9 @@ fn command_line_optional_dep_three_options() {
         .with_stderr_data(str![[r#"
 [UPDATING] `dummy-registry` index
 [LOCKING] 1 package to latest compatible version
-[ERROR] Package `a v0.1.0 ([ROOT]/foo)` does not have feature `bar`. It has an optional dependency with that name, but that dependency uses the "dep:" syntax in the features table, so it does not have an implicit feature with that name.
+[ERROR] package `a v0.1.0 ([ROOT]/foo)` does not have feature `bar`
+
+[HELP] an optional dependency with that name exists, but the `features` table includes it with the "dep:" syntax so it does not have an implicit feature with that name
 Dependency `bar` would be enabled by these features:
 	- `f1`
 	- `f2`
@@ -537,7 +541,9 @@ fn command_line_optional_dep_many_options() {
         .with_stderr_data(str![[r#"
 [UPDATING] `dummy-registry` index
 [LOCKING] 1 package to latest compatible version
-[ERROR] Package `a v0.1.0 ([ROOT]/foo)` does not have feature `bar`. It has an optional dependency with that name, but that dependency uses the "dep:" syntax in the features table, so it does not have an implicit feature with that name.
+[ERROR] package `a v0.1.0 ([ROOT]/foo)` does not have feature `bar`
+
+[HELP] an optional dependency with that name exists, but the `features` table includes it with the "dep:" syntax so it does not have an implicit feature with that name
 Dependency `bar` would be enabled by these features:
 	- `f1`
 	- `f2`
@@ -583,7 +589,9 @@ fn command_line_optional_dep_many_paths() {
         .with_stderr_data(str![[r#"
 [UPDATING] `dummy-registry` index
 [LOCKING] 1 package to latest compatible version
-[ERROR] Package `a v0.1.0 ([ROOT]/foo)` does not have feature `bar`. It has an optional dependency with that name, but that dependency uses the "dep:" syntax in the features table, so it does not have an implicit feature with that name.
+[ERROR] package `a v0.1.0 ([ROOT]/foo)` does not have feature `bar`
+
+[HELP] an optional dependency with that name exists, but the `features` table includes it with the "dep:" syntax so it does not have an implicit feature with that name
 Dependency `bar` would be enabled by these features:
 	- `f1`
 	- `f2`
@@ -820,7 +828,7 @@ m1-feature set
         .cwd("member2")
         .with_status(101)
         .with_stderr_data(str![[r#"
-[ERROR] Package `member1 v0.1.0 ([ROOT]/foo/member1)` does not have the feature `m2-feature`
+[ERROR] package `member1 v0.1.0 ([ROOT]/foo/member1)` does not have the feature `m2-feature`
 
 [HELP] a feature with a similar name exists: `m1-feature`