feat: add SourceMap::to_data_url (#81)

Cargo.toml

@@ -32,6 +32,7 @@ if_chain = "1.0.0"
 scroll = { version = "0.10.1", features = ["derive"], optional = true }
 data-encoding = "2.3.3"
 debugid = {version = "0.8.0", features = ["serde"] }
+base64-simd = { version = "0.7" }
 
 [build-dependencies]
 rustc_version = "0.2.3"

src/types.rs

@@ -520,6 +520,29 @@ impl SourceMap {
         encode(self, w)
     }
 
+    /// Encode a sourcemap into a data url.
+    ///
+    /// ```rust
+    /// # use sourcemap::SourceMap;
+    /// # let input: &[_] = b"{
+    /// #     \"version\":3,
+    /// #     \"sources\":[\"coolstuff.js\"],
+    /// #     \"names\":[\"x\",\"alert\"],
+    /// #     \"mappings\":\"AAAA,GAAIA,GAAI,EACR,IAAIA,GAAK,EAAG,CACVC,MAAM\"
+    /// # }";
+    /// let sm = SourceMap::from_reader(input).unwrap();
+    /// sm.to_data_url().unwrap();
+    /// ```
+    pub fn to_data_url(&self) -> Result<String> {
+        let mut buf = vec![];
+        encode(self, &mut buf)?;
+        let b64 = base64_simd::Base64::STANDARD.encode_to_boxed_str(&buf);
+        Ok(format!(
+            "data:application/json;charset=utf-8;base64,{}",
+            b64
+        ))
+    }
+
     /// Creates a sourcemap from a reader over a JSON byte slice in UTF-8
     /// format.  Optionally a "garbage header" as defined by the
     /// sourcemap draft specification is supported.  In case an indexed

tests/test_encoder.rs

@@ -18,3 +18,10 @@ fn test_basic_sourcemap() {
         assert_eq!(tok1, tok2);
     }
 }
+
+#[test]
+fn test_sourcemap_data_url() {
+    let input: &[_] = br#"{"version":3,"file":"build/foo.min.js","sources":["src/foo.js"],"names":[],"mappings":"AAAA","sourceRoot":"/"}"#;
+    let sm = SourceMap::from_reader(input).unwrap();
+    assert_eq!(sm.to_data_url().unwrap(), "data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJmaWxlIjoiYnVpbGQvZm9vLm1pbi5qcyIsInNvdXJjZXMiOlsic3JjL2Zvby5qcyJdLCJzb3VyY2VSb290IjoiLyIsIm5hbWVzIjpbXSwibWFwcGluZ3MiOiJBQUFBIn0=");
+}