diff --git a/scarb/tests/build_cairo_plugin.rs b/scarb/tests/build_cairo_plugin.rs
index ed58def42..f0db09332 100644
--- a/scarb/tests/build_cairo_plugin.rs
+++ b/scarb/tests/build_cairo_plugin.rs
@@ -1269,3 +1269,112 @@ fn executable_name_cannot_clash_attr() {
             error: duplicate expansions defined for procedural macro some v1.0.0 ([..]Scarb.toml): some
         "#});
 }
+
+#[test]
+fn can_be_expanded() {
+    let temp = TempDir::new().unwrap();
+    let t = temp.child("some");
+    CairoPluginProjectBuilder::default()
+        .lib_rs(indoc! {r##"
+        use cairo_lang_macro::{ProcMacroResult, TokenStream, attribute_macro, derive_macro};
+
+        #[attribute_macro]
+        pub fn some(_attr: TokenStream, token_stream: TokenStream) -> ProcMacroResult {
+            let token_stream = TokenStream::new(
+                token_stream
+                    .to_string()
+                    .replace("12", "34")
+            );
+            ProcMacroResult::new(token_stream)
+        }
+
+        #[derive_macro]
+        pub fn custom_derive(token_stream: TokenStream) -> ProcMacroResult {
+            let name = token_stream
+                .clone()
+                .to_string()
+                .lines()
+                .find(|l| l.starts_with("struct"))
+                .unwrap()
+                .to_string()
+                .replace("struct", "")
+                .replace("}", "")
+                .replace("{", "")
+                .trim()
+                .to_string();
+
+            let token_stream = TokenStream::new(indoc::formatdoc!{r#"
+                impl SomeImpl of Hello<{name}> {{
+                    fn world(self: @{name}) -> u32 {{
+                        32
+                    }}
+                }}
+            "#});
+
+            ProcMacroResult::new(token_stream)
+        }
+        "##})
+        .add_dep(r#"indoc = "*""#)
+        .build(&t);
+    let project = temp.child("hello");
+    ProjectBuilder::start()
+        .name("hello")
+        .version("1.0.0")
+        .dep("some", &t)
+        .lib_cairo(indoc! {r#"
+            trait Hello<T> {
+                fn world(self: @T) -> u32;
+            }
+
+            #[derive(CustomDerive, Drop)]
+            struct SomeType {}
+
+            #[some]
+            fn main() -> u32 {
+                let x = 12;
+                let a = SomeType {};
+                a.world() + x
+            }
+        "#})
+        .build(&project);
+
+    Scarb::quick_snapbox()
+        .arg("expand")
+        // Disable output from Cargo.
+        .env("CARGO_TERM_QUIET", "true")
+        .current_dir(&project)
+        .assert()
+        .success();
+
+    assert_eq!(
+        project.child("target/dev").files(),
+        vec!["hello.expanded.cairo"]
+    );
+    let expanded = project
+        .child("target/dev/hello.expanded.cairo")
+        .read_to_string();
+    snapbox::assert_eq(
+        indoc! {r#"
+        mod hello {
+            trait Hello<T> {
+                fn world(self: @T) -> u32;
+            }
+
+            #[derive(CustomDerive, Drop)]
+            struct SomeType {}
+            impl SomeTypeDrop of core::traits::Drop<SomeType>;
+            impl SomeImpl of Hello<SomeType> {
+                fn world(self: @SomeType) -> u32 {
+                    32
+                }
+            }
+            fn main() -> u32 {
+                let x = 34;
+                let a = SomeType {};
+                a.world() + x
+            }
+        }
+        "#},
+        expanded,
+    );
+}
diff --git a/scarb/tests/expand.rs b/scarb/tests/expand.rs
new file mode 100644
index 000000000..769c47149
--- /dev/null
+++ b/scarb/tests/expand.rs
@@ -0,0 +1,387 @@
+use assert_fs::fixture::PathChild;
+use assert_fs::TempDir;
+use indoc::{formatdoc, indoc};
+use itertools::Itertools;
+use scarb_test_support::command::Scarb;
+use scarb_test_support::fsx::ChildPathEx;
+use scarb_test_support::project_builder::ProjectBuilder;
+
+#[test]
+fn expand_package_simple() {
+    let t = TempDir::new().unwrap();
+    ProjectBuilder::start()
+        .name("hello")
+        .lib_cairo(indoc! {r#"
+            fn hello() -> felt252 {
+                0
+            }
+        "#})
+        .build(&t);
+
+    Scarb::quick_snapbox()
+        .arg("expand")
+        .current_dir(&t)
+        .assert()
+        .success()
+        .stdout_eq("");
+
+    assert_eq!(t.child("target").files(), vec!["CACHEDIR.TAG", "dev"]);
+    assert_eq!(t.child("target/dev").files(), vec!["hello.expanded.cairo"]);
+    let expanded = t.child("target/dev/hello.expanded.cairo").read_to_string();
+    snapbox::assert_eq(
+        indoc! {r#"
+        mod hello {
+            fn hello() -> felt252 {
+                0
+            }
+        }
+        "#},
+        expanded,
+    );
+}
+
+#[test]
+fn expand_integration_test() {
+    let t = TempDir::new().unwrap();
+    let test_case = indoc! {r#"
+        #[cfg(test)]
+        mod tests {
+            use hello::fib;
+
+            #[test]
+            fn it_works() {
+                assert(fib(16) == 987, 'it works!');
+            }
+        }
+    "#};
+    ProjectBuilder::start()
+        .name("hello")
+        .lib_cairo(formatdoc! {r#"
+            fn fib(mut n: u32) -> u32 {{
+                let mut a: u32 = 0;
+                let mut b: u32 = 1;
+                while n != 0 {{
+                    n = n - 1;
+                    let temp = b;
+                    b = a + b;
+                    a = temp;
+                }};
+                a
+            }}
+
+            {test_case}
+        "#})
+        .src("tests/a.cairo", test_case)
+        .src("tests/b.cairo", test_case)
+        .build(&t);
+    Scarb::quick_snapbox()
+        .arg("expand")
+        .arg("--target-name=hello_a")
+        .current_dir(&t)
+        .assert()
+        .success()
+        .stdout_eq("");
+    assert_eq!(
+        t.child("target/dev").files(),
+        vec!["hello_a.expanded.cairo"]
+    );
+    let expanded = t
+        .child("target/dev/hello_a.expanded.cairo")
+        .read_to_string();
+    snapbox::assert_eq(
+        indoc! {r#"
+        mod hello_integrationtest {
+            mod a {
+                mod tests {
+                    use hello::fib;
+
+                    #[test]
+                    fn it_works() {
+                        assert(fib(16) == 987, 'it works!');
+                    }
+                }
+            }
+        }
+        "#},
+        expanded,
+    );
+}
+
+#[test]
+fn can_select_target_by_kind() {
+    let t = TempDir::new().unwrap();
+    ProjectBuilder::start()
+        .name("hello")
+        .lib_cairo(indoc! {r#"
+            fn hello() -> felt252 {
+                42
+            }
+
+            #[cfg(test)]
+            mod tests {
+                use super::hello;
+
+                #[test]
+                fn it_works() {
+                    assert(hello() == 42, 'it works!');
+                }
+            }
+        "#})
+        .build(&t);
+    Scarb::quick_snapbox()
+        .arg("expand")
+        .arg("--target-kind=test")
+        .current_dir(&t)
+        .assert()
+        .success()
+        .stdout_eq("");
+    assert_eq!(
+        t.child("target/dev").files(),
+        vec!["hello_unittest.expanded.cairo"]
+    );
+    let expanded = t
+        .child("target/dev/hello_unittest.expanded.cairo")
+        .read_to_string();
+    snapbox::assert_eq(
+        indoc! {r#"
+            mod hello {
+                fn hello() -> felt252 {
+                    42
+                }
+
+                mod tests {
+                    use super::hello;
+
+                    #[test]
+                    fn it_works() {
+                        assert(hello() == 42, 'it works!');
+                    }
+                }
+            }
+        "#},
+        expanded,
+    );
+}
+
+#[test]
+fn can_expand_multiple_targets() {
+    let t = TempDir::new().unwrap();
+    let test_case = indoc! {r#"
+        #[cfg(test)]
+        mod tests {
+            use hello::fib;
+
+            #[test]
+            fn it_works() {
+                assert(fib(16) == 987, 'it works!');
+            }
+        }
+    "#};
+    ProjectBuilder::start()
+        .name("hello")
+        .lib_cairo(formatdoc! {r#"
+            fn fib(mut n: u32) -> u32 {{
+                let mut a: u32 = 0;
+                let mut b: u32 = 1;
+                while n != 0 {{
+                    n = n - 1;
+                    let temp = b;
+                    b = a + b;
+                    a = temp;
+                }};
+                a
+            }}
+
+            {test_case}
+        "#})
+        .src("tests/a.cairo", test_case)
+        .src("tests/b.cairo", test_case)
+        .build(&t);
+    Scarb::quick_snapbox()
+        .arg("expand")
+        .arg("--target-kind=test")
+        .current_dir(&t)
+        .assert()
+        .success()
+        .stdout_eq("");
+    assert_eq!(
+        t.child("target/dev")
+            .files()
+            .into_iter()
+            .sorted()
+            .collect_vec(),
+        vec![
+            "hello_a.expanded.cairo",
+            "hello_b.expanded.cairo",
+            "hello_unittest.expanded.cairo",
+        ]
+    );
+    let expanded = t
+        .child("target/dev/hello_unittest.expanded.cairo")
+        .read_to_string();
+    snapbox::assert_eq(
+        indoc! {r#"
+            mod hello {
+                fn fib(mut n: u32) -> u32 {
+                    let mut a: u32 = 0;
+                    let mut b: u32 = 1;
+                    while n != 0 {
+                        n = n - 1;
+                        let temp = b;
+                        b = a + b;
+                        a = temp;
+                    };
+                    a
+                }
+
+                mod tests {
+                    use hello::fib;
+
+                    #[test]
+                    fn it_works() {
+                        assert(fib(16) == 987, 'it works!');
+                    }
+                }
+            }
+        "#},
+        expanded,
+    );
+    let expanded = t
+        .child("target/dev/hello_a.expanded.cairo")
+        .read_to_string();
+    snapbox::assert_eq(
+        indoc! {r#"
+        mod hello_integrationtest {
+            mod a {
+                mod tests {
+                    use hello::fib;
+
+                    #[test]
+                    fn it_works() {
+                        assert(fib(16) == 987, 'it works!');
+                    }
+                }
+            }
+        }
+        "#},
+        expanded,
+    );
+    let expanded = t
+        .child("target/dev/hello_b.expanded.cairo")
+        .read_to_string();
+    snapbox::assert_eq(
+        indoc! {r#"
+        mod hello_integrationtest {
+            mod b {
+                mod tests {
+                    use hello::fib;
+
+                    #[test]
+                    fn it_works() {
+                        assert(fib(16) == 987, 'it works!');
+                    }
+                }
+            }
+        }
+        "#},
+        expanded,
+    );
+}
+
+#[test]
+fn selected_target_must_exist() {
+    let t = TempDir::new().unwrap();
+    ProjectBuilder::start()
+        .name("hello")
+        .lib_cairo(indoc! {r#"
+            fn hello() -> felt252 {
+                42
+            }
+        "#})
+        .build(&t);
+    Scarb::quick_snapbox()
+        .arg("expand")
+        .arg("--target-kind=non-existent")
+        .current_dir(&t)
+        .assert()
+        .failure()
+        .stdout_eq("error: no compilation units found for `hello`\n");
+}
+
+#[test]
+fn attempts_formatting() {
+    let t = TempDir::new().unwrap();
+    ProjectBuilder::start()
+        .name("hello")
+        .lib_cairo(indoc! {r#"
+            fn hello() -> felt252 {
+
+
+            42}
+            #[cfg(test)]
+            mod tests {
+                use super::hello;
+                #[test]
+                fn it_works() {
+
+
+                assert(hello() == 42, 'it works!');
+                                }
+            }
+        "#})
+        .build(&t);
+    Scarb::quick_snapbox()
+        .arg("expand")
+        .current_dir(&t)
+        .assert()
+        .success()
+        .stdout_eq("");
+    assert_eq!(t.child("target/dev").files(), vec!["hello.expanded.cairo"]);
+    let expanded = t.child("target/dev/hello.expanded.cairo").read_to_string();
+    // Defaults to lib target - hence no tests (stripped by config plugin).
+    snapbox::assert_eq(
+        indoc! {r#"
+            mod hello {
+                fn hello() -> felt252 {
+                    42
+                }
+            }
+        "#},
+        expanded,
+    );
+}
+
+#[test]
+fn can_skip_formatting() {
+    let t = TempDir::new().unwrap();
+    ProjectBuilder::start()
+        .name("hello")
+        .lib_cairo(indoc! {r#"
+            fn hello() -> felt252 {
+
+
+            42}
+        "#})
+        .build(&t);
+    Scarb::quick_snapbox()
+        .arg("expand")
+        .arg("--ugly")
+        .current_dir(&t)
+        .assert()
+        .success()
+        .stdout_eq("");
+    assert_eq!(t.child("target/dev").files(), vec!["hello.expanded.cairo"]);
+    let expanded = t.child("target/dev/hello.expanded.cairo").read_to_string();
+    snapbox::assert_eq(
+        indoc! {r#"
+
+            mod hello {
+            fn hello() -> felt252 {
+
+
+            42}
+            }
+        "#},
+        expanded,
+    );
+}