Add basic tests for local registry (#798)

These tests depend on both #790 and #793, hence they come in separate
PR.

---

**Stack**:
- #819
- #818
- #809
- #808
- #807
- #806
- #805
- #803
- #802
- #799
- #798 ⬅


⚠️ *Part of a stack created by [spr](https://github.com/ejoffe/spr). Do
not merge manually using the UI - doing so may have unexpected results.*

scarb/tests/local_registry.rs

@@ -6,7 +6,122 @@ use url::Url;
 
 use scarb_test_support::command::Scarb;
 use scarb_test_support::fsx::ChildPathEx;
-use scarb_test_support::project_builder::ProjectBuilder;
+use scarb_test_support::project_builder::{Dep, DepBuilder, ProjectBuilder};
+use scarb_test_support::registry::local::LocalRegistry;
+
+#[test]
+fn usage() {
+    let mut registry = LocalRegistry::create();
+    registry.publish(|t| {
+        ProjectBuilder::start()
+            .name("bar")
+            .version("1.0.0")
+            .lib_cairo(r#"fn f() -> felt252 { 0 }"#)
+            .build(t);
+    });
+
+    let t = TempDir::new().unwrap();
+    ProjectBuilder::start()
+        .name("foo")
+        .version("0.1.0")
+        .dep("bar", Dep.version("1").registry(&registry))
+        .lib_cairo(r#"fn f() -> felt252 { bar::f() }"#)
+        .build(&t);
+
+    // FIXME(mkaput): Why are verbose statuses not appearing here?
+    Scarb::quick_snapbox()
+        .arg("fetch")
+        .current_dir(&t)
+        .assert()
+        .success()
+        .stdout_matches(indoc! {r#"
+        [..] Unpacking bar v1.0.0 ([..])
+        "#});
+}
+
+#[test]
+fn not_found() {
+    let mut registry = LocalRegistry::create();
+    registry.publish(|t| {
+        // Publish a package so that the directory hierarchy is created.
+        // Note, however, that we declare a dependency on baZ.
+        ProjectBuilder::start()
+            .name("bar")
+            .version("1.0.0")
+            .lib_cairo(r#"fn f() -> felt252 { 0 }"#)
+            .build(t);
+    });
+
+    let t = TempDir::new().unwrap();
+    ProjectBuilder::start()
+        .name("foo")
+        .version("0.1.0")
+        .dep("baz", Dep.version("1").registry(&registry))
+        .build(&t);
+
+    Scarb::quick_snapbox()
+        .arg("fetch")
+        .current_dir(&t)
+        .assert()
+        .failure()
+        .stdout_matches(indoc! {r#"
+        error: package not found in registry: baz ^1 (registry+file://[..])
+        "#});
+}
+
+// TODO(mkaput): Test interdependencies.
+// TODO(mkaput): Test path dependencies overrides.
+
+#[test]
+fn empty_registry() {
+    let registry = LocalRegistry::create();
+
+    let t = TempDir::new().unwrap();
+    ProjectBuilder::start()
+        .name("foo")
+        .version("0.1.0")
+        .dep("baz", Dep.version("1").registry(&registry))
+        .build(&t);
+
+    Scarb::quick_snapbox()
+        .arg("fetch")
+        .current_dir(&t)
+        .assert()
+        .failure()
+        .stdout_matches(indoc! {r#"
+        error: package not found in registry: baz ^1 (registry+file://[..])
+        "#});
+}
+
+#[test]
+fn url_pointing_to_file() {
+    let registry_t = TempDir::new().unwrap();
+    let registry = registry_t.child("r");
+    registry.write_str("").unwrap();
+    let registry = Url::from_directory_path(&registry).unwrap().to_string();
+
+    let t = TempDir::new().unwrap();
+    ProjectBuilder::start()
+        .name("foo")
+        .version("0.1.0")
+        .dep("baz", Dep.version("1").registry(&registry))
+        .build(&t);
+
+    Scarb::quick_snapbox()
+        .arg("fetch")
+        .current_dir(&t)
+        .assert()
+        .failure()
+        .stdout_matches(indoc! {r#"
+        error: failed to load source: registry+file://[..]
+
+        Caused by:
+            local registry path is not a directory: [..]
+        "#});
+
+    // Prevent the temp directory from being deleted until this point.
+    drop(registry_t);
+}
 
 #[test]
 fn publish() {
@@ -149,4 +264,6 @@ fn publish_overwrites_existing() {
     );
 }
 
+// TODO(mkaput): Test errors properly when package is in index, but tarball is missing.
 // TODO(mkaput): Test publishing with target-specific dependencies.
+// TODO(mkaput): Test offline mode.

utils/scarb-test-support/src/lib.rs

@@ -6,4 +6,5 @@ pub mod fsx;
 pub mod gitx;
 pub mod manifest_edit;
 pub mod project_builder;
+pub mod registry;
 pub mod workspace_builder;

utils/scarb-test-support/src/registry/local.rs

@@ -0,0 +1,38 @@
+use std::fmt;
+
+use assert_fs::TempDir;
+use url::Url;
+
+use crate::command::Scarb;
+
+pub struct LocalRegistry {
+    pub t: TempDir,
+    pub url: String,
+}
+
+impl LocalRegistry {
+    pub fn create() -> Self {
+        let t = TempDir::new().unwrap();
+        let url = Url::from_directory_path(&t).unwrap().to_string();
+        Self { t, url }
+    }
+
+    pub fn publish(&mut self, f: impl FnOnce(&TempDir)) -> &mut Self {
+        let t = TempDir::new().unwrap();
+        f(&t);
+        Scarb::quick_snapbox()
+            .arg("publish")
+            .arg("--index")
+            .arg(&self.url)
+            .current_dir(&t)
+            .assert()
+            .success();
+        self
+    }
+}
+
+impl fmt::Display for LocalRegistry {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt::Display::fmt(&self.url, f)
+    }
+}

utils/scarb-test-support/src/registry/mod.rs

@@ -0,0 +1 @@
+pub mod local;