Allow the corpus to point to a single file

Cargo.toml

@@ -8,7 +8,7 @@ authors = ["Parity Technologies <admin@parity.io>"]
 license = "MIT/Apache-2.0"
 edition = "2024"
 repository = "https://github.com/paritytech/revive-differential-testing.git"
-rust-version = "1.85.0"
+rust-version = "1.88.0"
 
 [workspace.dependencies]
 revive-dt-common = { version = "0.1.0", path = "crates/common" }

crates/core/src/driver/mod.rs

@@ -101,12 +101,30 @@ where
             anyhow::bail!("unsupported solc version: {:?}", &mode.solc_version);
         };
 
+        // Note: if the metadata is contained within a solidity file then this is the only file that
+        // we wish to compile since this is a self-contained test. Otherwise, if it's a JSON file
+        // then we need to compile all of the contracts that are in the directory since imports are
+        // allowed in there.
+        let Some(ref metadata_file_path) = metadata.file_path else {
+            anyhow::bail!("The metadata file path is not defined");
+        };
+        let mut files_to_compile = if metadata_file_path
+            .extension()
+            .is_some_and(|extension| extension.eq_ignore_ascii_case("sol"))
+        {
+            Box::new(std::iter::once(metadata_file_path.clone())) as Box<dyn Iterator<Item = _>>
+        } else {
+            Box::new(
+                FilesWithExtensionIterator::new(metadata.directory()?)
+                    .with_allowed_extension("sol"),
+            )
+        };
+
         let compiler = Compiler::<T::Compiler>::new()
             .allow_path(metadata.directory()?)
             .solc_optimizer(mode.solc_optimize());
-        let mut compiler = FilesWithExtensionIterator::new(metadata.directory()?)
+        let mut compiler =
-            .with_allowed_extension("sol")
+            files_to_compile.try_fold(compiler, |compiler, path| compiler.with_source(&path))?;
-            .try_fold(compiler, |compiler, path| compiler.with_source(&path))?;
         for (library_instance, (library_address, _)) in self.deployed_libraries.iter() {
             let library_ident = &metadata
                 .contracts

crates/format/src/corpus.rs

@@ -28,13 +28,19 @@ impl Corpus {
     }
 }
 
-/// Recursively walks `path` and parses any JSON or Solidity file into a test
+/// If `path` is a file, try to parse it directly into a [MetadataFile].
-/// definition [Metadata].
+/// Else, recursively walk through the `path` directory and parse any
+/// JSON or Solidity file into a test definition [MetadataFile].
 ///
 /// Found tests are inserted into `tests`.
-///
-/// `path` is expected to be a directory.
 pub fn collect_metadata(path: &Path, tests: &mut Vec<MetadataFile>) {
+    if path.is_file()
+        && let Some(metadata) = MetadataFile::try_from_file(&path)
+    {
+        tests.push(metadata);
+        return;
+    }
+
     let dir_entry = match std::fs::read_dir(path) {
         Ok(dir_entry) => dir_entry,
         Err(error) => {
@@ -53,15 +59,6 @@ pub fn collect_metadata(path: &Path, tests: &mut Vec<MetadataFile>) {
         };
 
         let path = entry.path();
-        if path.is_dir() {
+        collect_metadata(&path, tests);
-            collect_metadata(&path, tests);
-            continue;
-        }
-
-        if path.is_file() {
-            if let Some(metadata) = MetadataFile::try_from_file(&path) {
-                tests.push(metadata)
-            }
-        }
     }
 }

crates/format/src/metadata.rs

@@ -193,7 +193,7 @@ impl Metadata {
                 metadata.file_path = Some(path.to_path_buf());
                 metadata.contracts = Some(
                     [(
-                        ContractInstance::new("test"),
+                        ContractInstance::new("Test"),
                         ContractPathAndIdent {
                             contract_source_path: path.to_path_buf(),
                             contract_ident: ContractIdent::new("Test"),