Discard fragments when parsing unnamed URLs (#3940)

## Summary

Closes https://github.com/astral-sh/uv/issues/3934.

crates/pep508-rs/src/verbatim_url.rs

@@ -155,6 +155,13 @@ impl VerbatimUrl {
     pub fn to_url(&self) -> Url {
         self.url.clone()
     }
+
+    /// Return the underlying [`Path`], if the URL is a file URL.
+    pub fn as_path(&self) -> Result<PathBuf, VerbatimUrlError> {
+        self.url
+            .to_file_path()
+            .map_err(|_| VerbatimUrlError::UrlConversion(self.url.to_file_path().unwrap()))
+    }
 }
 
 // This impl is written out because the `derive` doesn't seem to get it right.

crates/pypi-types/src/parsed_url.rs

@@ -59,8 +59,8 @@ impl UnnamedRequirementUrl for VerbatimParsedUrl {
     ) -> Result<Self, Self::Err> {
         let verbatim = VerbatimUrl::parse_path(&path, &working_dir)?;
         let parsed_path_url = ParsedPathUrl {
+            path: verbatim.as_path()?,
             url: verbatim.to_url(),
-            path: working_dir.as_ref().join(path),
             editable: false,
         };
         Ok(Self {
@@ -72,8 +72,8 @@ impl UnnamedRequirementUrl for VerbatimParsedUrl {
     fn parse_absolute_path(path: impl AsRef<Path>) -> Result<Self, Self::Err> {
         let verbatim = VerbatimUrl::parse_absolute_path(&path)?;
         let parsed_path_url = ParsedPathUrl {
+            path: verbatim.as_path()?,
             url: verbatim.to_url(),
-            path: path.as_ref().to_path_buf(),
             editable: false,
         };
         Ok(Self {

crates/requirements-txt/src/snapshots/requirements_txt__test__parse-unix-bare-url.txt.snap

@@ -21,7 +21,7 @@ RequirementsTxt {
                                     query: None,
                                     fragment: None,
                                 },
-                                path: "<REQUIREMENTS_DIR>/./scripts/packages/black_editable",
+                                path: "<REQUIREMENTS_DIR>/scripts/packages/black_editable",
                                 editable: false,
                             },
                         ),
@@ -70,7 +70,7 @@ RequirementsTxt {
                                     query: None,
                                     fragment: None,
                                 },
-                                path: "<REQUIREMENTS_DIR>/./scripts/packages/black_editable",
+                                path: "<REQUIREMENTS_DIR>/scripts/packages/black_editable",
                                 editable: false,
                             },
                         ),

crates/requirements-txt/src/snapshots/requirements_txt__test__parse-windows-bare-url.txt.snap

@@ -21,7 +21,7 @@ RequirementsTxt {
                                     query: None,
                                     fragment: None,
                                 },
-                                path: "<REQUIREMENTS_DIR>/./scripts/packages/black_editable",
+                                path: "<REQUIREMENTS_DIR>/scripts/packages/black_editable",
                                 editable: false,
                             },
                         ),
@@ -70,7 +70,7 @@ RequirementsTxt {
                                     query: None,
                                     fragment: None,
                                 },
-                                path: "<REQUIREMENTS_DIR>/./scripts/packages/black_editable",
+                                path: "<REQUIREMENTS_DIR>/scripts/packages/black_editable",
                                 editable: false,
                             },
                         ),

crates/uv/tests/pip_compile.rs

@@ -3442,6 +3442,60 @@ fn deduplicate_editable() -> Result<()> {
     Ok(())
 }
 
+#[test]
+fn strip_fragment_unnamed() -> Result<()> {
+    let context = TestContext::new("3.12");
+    let requirements_in = context.temp_dir.child("requirements.in");
+    requirements_in.write_str(indoc! {r"
+        ../../scripts/packages/black_editable#egg=black
+        "
+    })?;
+
+    uv_snapshot!(context.filters(), context.compile()
+        .arg(requirements_in.path())
+        .current_dir(current_dir()?), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    # This file was autogenerated by uv via the following command:
+    #    uv pip compile --cache-dir [CACHE_DIR] --exclude-newer 2024-03-25T00:00:00Z [TEMP_DIR]/requirements.in
+    ../../scripts/packages/black_editable#egg=black
+        # via -r [TEMP_DIR]/requirements.in
+
+    ----- stderr -----
+    Resolved 1 package in [TIME]
+    "###);
+
+    Ok(())
+}
+
+#[test]
+fn strip_fragment_named() -> Result<()> {
+    let context = TestContext::new("3.12");
+    let requirements_in = context.temp_dir.child("requirements.in");
+    requirements_in.write_str(indoc! {r"
+        black @ ../../scripts/packages/black_editable#egg=black
+        "
+    })?;
+
+    uv_snapshot!(context.filters(), context.compile()
+        .arg(requirements_in.path())
+        .current_dir(current_dir()?), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    # This file was autogenerated by uv via the following command:
+    #    uv pip compile --cache-dir [CACHE_DIR] --exclude-newer 2024-03-25T00:00:00Z [TEMP_DIR]/requirements.in
+    ../../scripts/packages/black_editable#egg=black
+        # via -r [TEMP_DIR]/requirements.in
+
+    ----- stderr -----
+    Resolved 1 package in [TIME]
+    "###);
+
+    Ok(())
+}
+
 #[test]
 fn recursive_extras_direct_url() -> Result<()> {
     let context = TestContext::new("3.12");