Cairo plugin as a shared library

Cargo.toml

@@ -1,29 +1,17 @@
 [package]
-name = "hello-cairo-plugin"
-version = "0.0.0"
+name = "hello_plugin"
+version = "1.0.0"
 edition = "2021"
 
+[lib]
+crate-type = ["cdylib"]
+
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-anyhow = "1.0.75"
-cairo-lang-compiler = "2.4.1"
-cairo-lang-defs = "2.4.1"
-cairo-lang-runner = "2.4.1"
-cairo-lang-semantic = "2.4.1"
-cairo-lang-sierra = "2.4.1"
-cairo-lang-starknet = "2.4.1"
-cairo-lang-syntax = "2.4.1"
-cairo-lang-utils = "2.4.1"
-camino = "1.1.6"
-clap = "4.4.8"
-indoc = "2.0.4"
-scarb = { git = "https://github.com/software-mansion/scarb", tag = "v2.4.1", version = "2.4.1" }
-scarb-metadata = "1.8.0"
-scarb-ui = "0.1.0"
-semver = "1.0.20"
-serde = "1.0.193"
-serde_json = "1.0.108"
-smol_str = "0.2.0"
-tracing = "0.1.40"
-url = "2.5.0"
+cairo-lang-macro = "0.1.0"
+cairo-lang-defs = "2.8.2"
+cairo-lang-diagnostics = "2.8.2"
+cairo-lang-parser = "2.8.2"
+cairo-lang-syntax = "2.8.2"
+regex = "1.10.6"

Scarb.toml

@@ -1,5 +1,5 @@
 [package]
-name = "hello"
-version = "0.0.0"
+name = "hello_plugin"
+version = "1.0.0"
 
 [cairo-plugin]

examples/cairo/Scarb.lock

@@ -5,9 +5,9 @@ version = 1
 name = "examples"
 version = "0.1.0"
 dependencies = [
- "hello",
+ "hello_plugin",
 ]
 
 [[package]]
-name = "hello"
-version = "0.0.0"
+name = "hello_plugin"
+version = "1.0.0"

examples/cairo/Scarb.toml

@@ -9,14 +9,11 @@ sierra = true
 
 [dependencies]
 ## Referencing using local package:
-hello = { path = "../../" }
+hello_plugin = { path = "../../" }
 
 ## Referencing using git:
 # hello = { git = "https://github.com/piwonskp/hello-cairo-plugin", crate = "hello" }
 
 ## Referencing compiled as part of this project:
 ## As for scarb 2.4.0 this is still an unsupported feature
 # hello = ">=0.1.0"
-
-
-[[target.hello]]

src/lib.rs

@@ -0,0 +1,77 @@
+use cairo_lang_macro::{
+    attribute_macro, Diagnostic, Diagnostics, ProcMacroResult, TokenStream,
+};
+use cairo_lang_diagnostics::FormattedDiagnosticEntry;
+use cairo_lang_parser::utils::SimpleParserDatabase;
+use cairo_lang_syntax::node::ast::{ModuleItem, SyntaxFile};
+use cairo_lang_syntax::node::TypedSyntaxNode;
+use core::ops::Deref;
+use regex::Regex;
+
+
+fn parser_to_macro_diagnostic(entry: &FormattedDiagnosticEntry) -> Diagnostic {
+    let severity = match entry.severity() {
+        cairo_lang_diagnostics::Severity::Error => cairo_lang_macro::Severity::Error,
+        cairo_lang_diagnostics::Severity::Warning => cairo_lang_macro::Severity::Warning,
+    };
+    Diagnostic {
+        message: entry.message().to_string(),
+        severity: severity,
+    }
+}
+
+/// Insert hello at the begining of the function using fully fledged cairo parser  
+#[attribute_macro]
+pub fn hello(_attrs: TokenStream, token_stream: TokenStream) -> ProcMacroResult {
+    let db = SimpleParserDatabase::default();
+
+    let (parsed_node, parser_diagnostics) = db.parse_virtual_with_diagnostics(token_stream);
+    let formatted_diags = parser_diagnostics.format_with_severity(&db);
+    let diagnostics = formatted_diags.iter().map(parser_to_macro_diagnostic);
+
+    let module_items = SyntaxFile::from_syntax_node(&db, parsed_node)
+        .items(&db)
+        .deref()
+        .elements(&db);
+    let function = match module_items.as_slice() {
+        [ModuleItem::FreeFunction(fun)] => fun,
+        // Currently attribute macros are run only on functions so the code should never reach this place
+        _ => panic!("hello attribute may be set on functions only"),
+    };
+
+    let instrumented_function = format!(
+        "
+        {} {{
+            core::debug::print_felt252('Hello from ast, {}!');
+            {}
+        }}
+        ",
+        function.declaration(&db).as_syntax_node().get_text(&db),
+        function
+            .declaration(&db)
+            .name(&db)
+            .as_syntax_node()
+            .get_text(&db),
+        function.body(&db).as_syntax_node().get_text(&db)
+    );
+
+    ProcMacroResult::new(TokenStream::new(instrumented_function))
+        .with_diagnostics(Diagnostics::new(diagnostics.collect()))
+}
+
+
+/// A lightweight version of hello macro using regex
+#[attribute_macro]
+pub fn hello_regex(_attrs: TokenStream, token_stream: TokenStream) -> ProcMacroResult {
+    let fn_regex =
+        Regex::new(r"^(\s*fn\s+(?<function_name>\w+)\s*\(.*?\)\s*(->\s*.*)?\{)").unwrap();
+    let function = token_stream.to_string();
+    let instrumented = fn_regex.replace_all(&function, |caps: &regex::Captures| {
+        format!(
+            "{}\n\tcore::debug::print_felt252('Hello {}!');",
+            &caps[0], &caps["function_name"]
+        )
+    });
+
+    ProcMacroResult::new(TokenStream::new(instrumented.to_string()))
+}