Speed up dependency builds by allowing parallelism

Author: oli-obk

src/dependencies.rs

@@ -385,7 +385,14 @@ impl Default for DependencyBuilder {
     fn default() -> Self {
         Self {
             crate_manifest_path: PathBuf::from("Cargo.toml"),
-            program: CommandBuilder::cargo(),
+            program: CommandBuilder {
+                // We don't need any of the other flags that are useful by default
+                // for running cargo in ui_tests. The dependency builder output
+                // is never recorded into .stderr files, so colors, ordering
+                // and verbosity is not important.
+                args: vec!["build".into()],
+                ..CommandBuilder::cargo()
+            },
             build_std: None,
             bless_lockfile: false,
         }

tests/integrations/dep-fail/Cargo.stdout

@@ -7,9 +7,10 @@ Building dependencies ... FAILED
 tests/ui/basic_test.rs ... FAILED
 
 FAILED TEST: tests/ui/basic_test.rs
-command: "$CMD" "build" "--color=never" "--quiet" "--jobs" "1" "--target-dir" "$DIR/tests/integrations/dep-fail/target/ui/0" "--manifest-path" "tested_crate/Cargo.toml"  "--message-format=json"
+command: "$CMD" "build" "--target-dir" "$DIR/tests/integrations/dep-fail/target/ui/0" "--manifest-path" "tested_crate/Cargo.toml"  "--message-format=json"
 
 full stderr:
+   Compiling tested_crate v0.1.0-dev ($DIR/tests/integrations/dep-fail/tested_crate)
 error: could not compile `tested_crate` (lib) due to 1 previous error
 
 full stdout:

tests/integrations/dep-fail/Cargo.toml

@@ -1,3 +1,5 @@
+#@normalize-stdout-test: " *Blocking waiting for file lock on package cache\n" -> ""
+
 [package]
 name = "compile_test"
 version = "0.1.0"