resolc crate (#328)

- Factor the YUL crate out of `revive-solidity`.
- `revive-solidity` is in reality not a Solidity implementation but the
revive solidity compiler driver (`resolc`). By renaming we not only get
this straight but also a binary with the same name as the crate which
should be less confusing.

---------

Signed-off-by: Cyrill Leutwiler <bigcyrill@hotmail.com>

crates/resolc/src/tests/libraries.rs

@@ -0,0 +1,90 @@
+//! The Solidity compiler unit tests for libraries.
+
+#![cfg(test)]
+
+use std::collections::BTreeMap;
+
+pub const LIBRARY_TEST_SOURCE: &str = r#"
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.0;
+
+// A simple library with at least one external method
+library SimpleLibrary {
+    function add(uint256 a, uint256 b) external pure returns (uint256) {
+        return a + b;
+    }
+}
+
+// A contract calling that library
+contract SimpleContract {
+    using SimpleLibrary for uint256;
+
+    function performAlgorithm(uint256 a, uint256 b) public pure returns (uint256) {
+        uint sum = 0;
+        if (a > b) {
+            while (true) {
+                sum += a.add(b);
+            }
+        }
+        return sum;
+    }
+}
+    "#;
+
+#[test]
+fn not_specified() {
+    let mut sources = BTreeMap::new();
+    sources.insert("test.sol".to_owned(), LIBRARY_TEST_SOURCE.to_owned());
+
+    let output =
+        super::build_solidity_and_detect_missing_libraries(sources.clone(), BTreeMap::new())
+            .expect("Test failure");
+    assert!(
+        output
+            .contracts
+            .as_ref()
+            .expect("Always exists")
+            .get("test.sol")
+            .expect("Always exists")
+            .get("SimpleContract")
+            .expect("Always exists")
+            .missing_libraries
+            .as_ref()
+            .expect("Always exists")
+            .contains("test.sol:SimpleLibrary"),
+        "Missing library not detected"
+    );
+}
+
+#[test]
+fn specified() {
+    let mut sources = BTreeMap::new();
+    sources.insert("test.sol".to_owned(), LIBRARY_TEST_SOURCE.to_owned());
+
+    let mut libraries = BTreeMap::new();
+    libraries
+        .entry("test.sol".to_string())
+        .or_insert_with(BTreeMap::new)
+        .entry("SimpleLibrary".to_string())
+        .or_insert("0x00000000000000000000000000000000DEADBEEF".to_string());
+
+    let output =
+        super::build_solidity_and_detect_missing_libraries(sources.clone(), libraries.clone())
+            .expect("Test failure");
+    assert!(
+        output
+            .contracts
+            .as_ref()
+            .expect("Always exists")
+            .get("test.sol")
+            .expect("Always exists")
+            .get("SimpleContract")
+            .expect("Always exists")
+            .missing_libraries
+            .as_ref()
+            .cloned()
+            .unwrap_or_default()
+            .is_empty(),
+        "The list of missing libraries must be empty"
+    );
+}