fix: source parsing for local paths

ethers-contract/ethers-contract-abigen/src/contract.rs

@@ -151,7 +151,8 @@ impl Context {
     /// Create a context from the code generation arguments.
     pub fn from_abigen(args: Abigen) -> Result<Self> {
         // get the actual ABI string
-        let abi_str = args.abi_source.get().context("failed to get ABI JSON")?;
+        let abi_str =
+            args.abi_source.get().map_err(|e| anyhow!("failed to get ABI JSON: {}", e))?;
         let mut abi_parser = AbiParser::default();
 
         let (abi, human_readable): (Abi, _) = if let Ok(abi) = abi_parser.parse_str(&abi_str) {

ethers-contract/ethers-contract-abigen/src/source.rs

@@ -60,7 +60,7 @@ impl Source {
         if matches!(source.chars().next(), Some('[' | '{')) {
             return Ok(Source::String(source.to_owned()))
         }
-        let root = env::current_dir()?.canonicalize()?;
+        let root = env::var("CARGO_MANIFEST_DIR")?;
         Source::with_root(root, source)
     }
 
@@ -72,6 +72,7 @@ impl Source {
         P: AsRef<Path>,
         S: AsRef<str>,
     {
+        let source = source.as_ref();
         let root = root.as_ref();
         cfg_if! {
             if #[cfg(target_arch = "wasm32")] {
@@ -87,10 +88,10 @@ impl Source {
                     .map_err(|_| anyhow!("root path '{}' is not absolute", root.display()))?;
             }
         }
-        let url = base.join(source.as_ref())?;
+        let url = base.join(source)?;
 
         match url.scheme() {
-            "file" => Ok(Source::local(url.path().to_string())),
+            "file" => Ok(Source::local(source.to_string())),
             "http" | "https" => match url.host_str() {
                 Some("etherscan.io") => Source::etherscan(
                     url.path()