Fix formatting of negated singleton versions in error messages (#836)

Closes #805 
Requires astral-sh/pubgrub#17

Cargo.toml

@@ -52,7 +52,7 @@ owo-colors = { version = "3.5.0" }
 petgraph = { version = "0.6.4" }
 platform-info = { version = "2.0.2" }
 plist = { version = "1.6.0" }
-pubgrub = { git = "https://github.com/zanieb/pubgrub", rev = "78b8add6942766e5fb070bbda1de570e93d6399f" }
+pubgrub = { git = "https://github.com/zanieb/pubgrub", rev = "866c0f2a87fee1e8abe804d40a2ee934de0973d7" }
 pyo3 = { version = "0.20.2" }
 pyo3-log = { version = "0.9.0"}
 pyproject-toml = { version = "0.8.1" }

crates/puffin-cli/tests/pip_install_scenarios.rs

@@ -262,7 +262,7 @@ fn dependency_excludes_range_of_compatible_versions() -> Result<()> {
 
               Because there is no version of c available matching <1.0.0 | >1.0.0, <2.0.0 | >2.0.0 and c==1.0.0 depends on a<2.0.0, c<2.0.0 depends on a<2.0.0.
               And because c==2.0.0 depends on a>=3.0.0, c depends on a<2.0.0 | >=3.0.0.
-              And because a<2.0.0 depends on b==1.0.0 (1), a Not ( ==3.0.0 ), c *, b Not ( ==1.0.0 ) are incompatible.
+              And because a<2.0.0 depends on b==1.0.0 (1), a!=3.0.0, c*, b!=1.0.0 are incompatible.
               And because a==3.0.0 depends on b==3.0.0, c depends on b<=1.0.0 | >=3.0.0.
               And because root depends on c and root depends on b>=2.0.0, <3.0.0, version solving failed.
         "###);
@@ -1466,7 +1466,7 @@ fn requires_transitive_prerelease_and_stable_dependency_many_versions() -> Resul
           × No solution found when resolving dependencies:
           ╰─▶ Because there is no version of b available matching <1.0.0 | >1.0.0 and b==1.0.0 depends on c, b depends on c.
               And because there is no version of c available matching >=2.0.0b1, b depends on c<2.0.0b1.
-              And because a==1.0.0 depends on c>=2.0.0b1 and there is no version of a available matching <1.0.0 | >1.0.0, b *, a * are incompatible.
+              And because a==1.0.0 depends on c>=2.0.0b1 and there is no version of a available matching <1.0.0 | >1.0.0, b*, a* are incompatible.
               And because root depends on b and root depends on a, version solving failed.
 
               hint: c was requested with a pre-release marker (e.g., >=2.0.0b1), but pre-releases weren't enabled (try: `--prerelease=allow`)
@@ -2051,7 +2051,7 @@ fn requires_transitive_incompatible_with_transitive() -> Result<()> {
         ----- stderr -----
           × No solution found when resolving dependencies:
           ╰─▶ Because there is no version of b available matching <1.0.0 | >1.0.0 and b==1.0.0 depends on c==2.0.0, b depends on c==2.0.0.
-              And because a==1.0.0 depends on c==1.0.0 and there is no version of a available matching <1.0.0 | >1.0.0, a *, b * are incompatible.
+              And because a==1.0.0 depends on c==1.0.0 and there is no version of a available matching <1.0.0 | >1.0.0, a*, b* are incompatible.
               And because root depends on b and root depends on a, version solving failed.
         "###);
     });
@@ -2447,11 +2447,11 @@ fn requires_python_version_greater_than_current_excluded() -> Result<()> {
 
         ----- stderr -----
           × No solution found when resolving dependencies:
-          ╰─▶ Because there is no version of Python available matching >=3.10, <3.11 and there is no version of Python available matching >=3.12, Python >=3.10, <3.11 | >=3.12 are incompatible.
-              And because there is no version of Python available matching >=3.11, <3.12, Python >=3.10 are incompatible.
+          ╰─▶ Because there is no version of Python available matching >=3.10, <3.11 and there is no version of Python available matching >=3.12, Python>=3.10, <3.11 | >=3.12 are incompatible.
+              And because there is no version of Python available matching >=3.11, <3.12, Python>=3.10 are incompatible.
               And because a==2.0.0 depends on Python>=3.10 and there is no version of a available matching >2.0.0, <3.0.0 | >3.0.0, <4.0.0 | >4.0.0, a>=2.0.0, <3.0.0 is forbidden. (1)
 
-              Because there is no version of Python available matching >=3.11, <3.12 and there is no version of Python available matching >=3.12, Python >=3.11 are incompatible.
+              Because there is no version of Python available matching >=3.11, <3.12 and there is no version of Python available matching >=3.12, Python>=3.11 are incompatible.
               And because a==3.0.0 depends on Python>=3.11, a==3.0.0 is forbidden.
               And because a>=2.0.0, <3.0.0 is forbidden (1), a>=2.0.0, <4.0.0 is forbidden. (2)
 

crates/puffin-resolver/src/pubgrub/report.rs

@@ -125,7 +125,10 @@ impl ReportFormatter<PubGrubPackage, Range<PubGrubVersion>> for PubGrubReportFor
                 &External::FromDependencyOf((*p2).clone(), r2.clone(), (*p1).clone(), r1.clone()),
             ),
             slice => {
-                let str_terms: Vec<_> = slice.iter().map(|(p, t)| format!("{p} {t}")).collect();
+                let str_terms: Vec<_> = slice
+                    .iter()
+                    .map(|(p, t)| format!("{p}{}", PubGrubTerm::from_term((*t).clone())))
+                    .collect();
                 str_terms.join(", ") + " are incompatible"
             }
         }
@@ -232,3 +235,29 @@ impl std::fmt::Display for PubGrubHint {
         }
     }
 }
+
+/// A derivative of the [Term] type with custom formatting.
+struct PubGrubTerm {
+    inner: Term<Range<PubGrubVersion>>,
+}
+
+impl std::fmt::Display for PubGrubTerm {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match &self.inner {
+            Term::Positive(set) => write!(f, "{set}"),
+            Term::Negative(set) => {
+                if let Some(version) = set.as_singleton() {
+                    write!(f, "!={version}")
+                } else {
+                    write!(f, "!( {set} )")
+                }
+            }
+        }
+    }
+}
+
+impl PubGrubTerm {
+    fn from_term(term: Term<Range<PubGrubVersion>>) -> PubGrubTerm {
+        PubGrubTerm { inner: term }
+    }
+}