fix: edge cases for matchspec parsing (#217)

crates/rattler_conda_types/src/match_spec/mod.rs

@@ -72,7 +72,7 @@ use matcher::StringMatcher;
 ///
 /// let spec = MatchSpec::from_str("foo=1.0=py27_0").unwrap();
 /// assert_eq!(spec.name, Some("foo".to_string()));
-/// assert_eq!(spec.version, Some(VersionSpec::from_str("1.0.*").unwrap()));
+/// assert_eq!(spec.version, Some(VersionSpec::from_str("==1.0").unwrap()));
 /// assert_eq!(spec.build, Some(StringMatcher::from_str("py27_0").unwrap()));
 ///
 /// let spec = MatchSpec::from_str("conda-forge::foo[version=\"1.0.*\"]").unwrap();

crates/rattler_conda_types/src/match_spec/parse.rs

@@ -373,6 +373,30 @@ fn parse(input: &str) -> Result<MatchSpec, ParseMatchSpecError> {
             Cow::Borrowed(version_str)
         };
 
+        // Special case handling for version strings that start with `=`.
+        let version_str = if let (Some(version_str), true) =
+            (version_str.strip_prefix("=="), build_str.is_none())
+        {
+            // If the version starts with `==` and the build string is none we strip the `==` part.
+            Cow::Borrowed(version_str)
+        } else if let Some(version_str_part) = version_str.strip_prefix('=') {
+            let not_a_group = !version_str_part.contains(['=', ',', '|']);
+            if not_a_group {
+                // If the version starts with `=`, is not part of a group (e.g. 1|2) we append a *
+                // if it doesnt have one already.
+                if build_str.is_none() && !version_str_part.ends_with('*') {
+                    Cow::Owned(format!("{version_str_part}*"))
+                } else {
+                    Cow::Borrowed(version_str_part)
+                }
+            } else {
+                // Version string is part of a group, return the non-stripped version string
+                version_str
+            }
+        } else {
+            version_str
+        };
+
         // Parse the version spec
         match_spec.version = Some(
             VersionSpec::from_str(version_str.as_ref())
@@ -389,6 +413,8 @@ fn parse(input: &str) -> Result<MatchSpec, ParseMatchSpecError> {
 
 #[cfg(test)]
 mod tests {
+    use serde::Serialize;
+    use std::collections::BTreeMap;
     use std::str::FromStr;
 
     use super::{
@@ -462,27 +488,6 @@ mod tests {
         assert_eq!(split_version_and_build("* *"), Ok(("*", Some("*"))));
     }
 
-    #[test]
-    fn test_match_spec() {
-        insta::assert_yaml_snapshot!([
-            MatchSpec::from_str("python 3.8.* *_cpython").unwrap(),
-            MatchSpec::from_str("foo=1.0=py27_0").unwrap(),
-            MatchSpec::from_str("foo==1.0=py27_0").unwrap(),
-        ],
-        @r###"
-        ---
-        - name: python
-          version: 3.8.*
-          build: "*_cpython"
-        - name: foo
-          version: 1.0.*
-          build: py27_0
-        - name: foo
-          version: "==1.0"
-          build: py27_0
-        "###);
-    }
-
     #[test]
     fn test_nameless_match_spec() {
         insta::assert_yaml_snapshot!([
@@ -566,4 +571,39 @@ mod tests {
             &[("version", "1.3,2.0")]
         );
     }
+
+    #[test]
+    fn test_from_str() {
+        // A list of matchspecs to parse.
+        // Please keep this list sorted.
+        let specs = [
+            "blas *.* mkl",
+            "foo=1.0=py27_0",
+            "foo==1.0=py27_0",
+            "python 3.8.* *_cpython",
+            "pytorch=*=cuda*",
+        ];
+
+        #[derive(Serialize)]
+        #[serde(untagged)]
+        enum MatchSpecOrError {
+            Error { error: String },
+            MatchSpec(MatchSpec),
+        }
+
+        let evaluated: BTreeMap<_, _> = specs
+            .iter()
+            .map(|spec| {
+                (
+                    spec,
+                    MatchSpec::from_str(spec)
+                        .map(MatchSpecOrError::MatchSpec)
+                        .unwrap_or_else(|err| MatchSpecOrError::Error {
+                            error: err.to_string(),
+                        }),
+                )
+            })
+            .collect();
+        insta::assert_yaml_snapshot!("parsed matchspecs", evaluated);
+    }
 }

crates/rattler_conda_types/src/match_spec/snapshots/rattler_conda_types__match_spec__parse__tests__parsed matchspecs.snap

@@ -0,0 +1,25 @@
+---
+source: crates/rattler_conda_types/src/match_spec/parse.rs
+expression: evaluated
+---
+blas *.* mkl:
+  name: blas
+  version: "*"
+  build: mkl
+foo=1.0=py27_0:
+  name: foo
+  version: "==1.0"
+  build: py27_0
+foo==1.0=py27_0:
+  name: foo
+  version: "==1.0"
+  build: py27_0
+python 3.8.* *_cpython:
+  name: python
+  version: 3.8.*
+  build: "*_cpython"
+pytorch=*=cuda*:
+  name: pytorch
+  version: "*"
+  build: cuda*
+

crates/rattler_conda_types/src/version_spec/version_tree.rs

@@ -88,8 +88,8 @@ fn recognize_constraint<'a, E: ParseError<&'a str> + ContextError<&'a str>>(
     input: &'a str,
 ) -> Result<(&'a str, &'a str), nom::Err<E>> {
     alt((
-        // Any
-        tag("*"),
+        // Any (* or *.*)
+        terminated(tag("*"), cut(opt(tag(".*")))),
         // Regex
         recognize(delimited(tag("^"), not(tag("$")), tag("$"))),
         // Version with optional operator followed by optional glob.