Try installing exact versions before updating

Cargo.toml

@@ -53,7 +53,7 @@ percent-encoding = "2.0"
 remove_dir_all = "0.5.2"
 rustfix = "0.5.0"
 same-file = "1"
-semver = { version = "0.9.0", features = ["serde"] }
+semver = { git = "https://github.com/illicitonion/semver.git", rev = "f1f912703f67ed63b751c525839731a90239bdcf", features = ["serde"] }
 serde = { version = "1.0.82", features = ["derive"] }
 serde_ignored = "0.1.0"
 serde_json = { version = "1.0.30", features = ["raw_value"] }

crates/resolver-tests/src/lib.rs

@@ -738,8 +738,8 @@ fn meta_test_deep_pretty_print_registry() {
         "vec![pkg!((\"foo\", \"1.0.1\") => [dep_req(\"bar\", \"^1\"),]),\
          pkg!((\"foo\", \"1.0.0\") => [dep_req(\"bar\", \"^2\"),]),\
          pkg!((\"foo\", \"2.0.0\") => [dep(\"bar\"),]),\
-         pkg!((\"bar\", \"1.0.0\") => [dep_req(\"baz\", \"= 1.0.2\"),dep_req(\"other\", \"^1\"),]),\
-         pkg!((\"bar\", \"2.0.0\") => [dep_req(\"baz\", \"= 1.0.1\"),]),\
+         pkg!((\"bar\", \"1.0.0\") => [dep_req(\"baz\", \"=1.0.2\"),dep_req(\"other\", \"^1\"),]),\
+         pkg!((\"bar\", \"2.0.0\") => [dep_req(\"baz\", \"=1.0.1\"),]),\
          pkg!((\"baz\", \"1.0.2\") => [dep_req(\"other\", \"^2\"),]),\
          pkg!((\"baz\", \"1.0.1\")),\
          pkg!((\"cat\", \"1.0.2\") => [dep_req_kind(\"other\", \"^2\", DepKind::Build, false),]),\

src/cargo/ops/cargo_install.rs

@@ -151,7 +151,7 @@ fn install_one(
             krate,
             vers,
             config,
-            true,
+            NeedsUpdate::True,
             &mut |git| git.read_packages(),
         )?
     } else if source_id.is_path() {
@@ -180,7 +180,7 @@ fn install_one(
             }
         }
         src.update()?;
-        select_pkg(src, krate, vers, config, false, &mut |path| {
+        select_pkg(src, krate, vers, config, NeedsUpdate::False, &mut |path| {
             path.read_packages()
         })?
     } else {
@@ -189,7 +189,11 @@ fn install_one(
             krate,
             vers,
             config,
-            is_first_install,
+            if is_first_install {
+                NeedsUpdate::TryWithoutFirst
+            } else {
+                NeedsUpdate::False
+            },
             &mut |_| {
                 bail!(
                     "must specify a crate to install from \

src/cargo/ops/cargo_uninstall.rs

@@ -85,7 +85,7 @@ fn uninstall_cwd(root: &Filesystem, bins: &[String], config: &Config) -> CargoRe
     let tracker = InstallTracker::load(config, root)?;
     let source_id = SourceId::for_path(config.cwd())?;
     let src = path_source(source_id, config)?;
-    let pkg = select_pkg(src, None, None, config, true, &mut |path| {
+    let pkg = select_pkg(src, None, None, config, NeedsUpdate::True, &mut |path| {
         path.read_packages()
     })?;
     let pkgid = pkg.package_id();

src/cargo/ops/common_for_install_and_uninstall.rs

@@ -525,13 +525,20 @@ pub fn path_source(source_id: SourceId, config: &Config) -> CargoResult<PathSour
     Ok(PathSource::new(&path, source_id, config))
 }
 
+#[derive(Clone, Copy, PartialEq, Eq)]
+pub enum NeedsUpdate {
+    True,
+    False,
+    TryWithoutFirst,
+}
+
 /// Gets a Package based on command-line requirements.
 pub fn select_pkg<'a, T>(
     mut source: T,
     name: Option<&str>,
     vers: Option<&str>,
     config: &Config,
-    needs_update: bool,
+    needs_update: NeedsUpdate,
     list_all: &mut dyn FnMut(&mut T) -> CargoResult<Vec<Package>>,
 ) -> CargoResult<Package>
 where
@@ -542,7 +549,7 @@ where
     // with other global Cargos
     let _lock = config.acquire_package_cache_lock()?;
 
-    if needs_update {
+    if let NeedsUpdate::True = needs_update {
         source.update()?;
     }
 
@@ -603,8 +610,21 @@ where
             vers
         };
         let dep = Dependency::parse_no_deprecated(name, vers_spec, source.source_id())?;
-        let deps = source.query_vec(&dep)?;
-        match deps.iter().map(|p| p.package_id()).max() {
+        let deps = (|| {
+            if let Some(vers_spec) = vers_spec {
+                if semver::VersionReq::parse(vers_spec).unwrap().is_exact() {
+                    let deps = source.query_vec(&dep)?;
+                    if deps.len() == 1 {
+                        return Ok(deps);
+                    }
+                }
+            }
+            if needs_update != NeedsUpdate::False {
+                source.update()?;
+            }
+            source.query_vec(&dep)
+        })();
+        match deps?.iter().map(|p| p.package_id()).max() {
             Some(pkgid) => {
                 let pkg = Box::new(&mut source).download_now(pkgid, config)?;
                 Ok(pkg)

tests/testsuite/build.rs

@@ -993,7 +993,7 @@ fn incompatible_dependencies() {
 error: failed to select a version for `bad`.
     ... required by package `qux v0.1.0`
     ... which is depended on by `foo v0.0.1 ([..])`
-versions that meet the requirements `>= 1.0.1` are: 1.0.2, 1.0.1
+versions that meet the requirements `>=1.0.1` are: 1.0.2, 1.0.1
 
 all possible versions conflict with previously selected packages.
 
@@ -1038,7 +1038,7 @@ fn incompatible_dependencies_with_multi_semver() {
             "\
 error: failed to select a version for `bad`.
     ... required by package `foo v0.0.1 ([..])`
-versions that meet the requirements `>= 1.0.1, <= 2.0.0` are: 2.0.0, 1.0.1
+versions that meet the requirements `>=1.0.1, <=2.0.0` are: 2.0.0, 1.0.1
 
 all possible versions conflict with previously selected packages.
 

tests/testsuite/install_upgrade.rs

@@ -225,8 +225,7 @@ fn ambiguous_version_no_longer_allowed() {
     cargo_process("install foo --version=1.0")
         .with_stderr(
             "\
-[UPDATING] `[..]` index
-[ERROR] the `--vers` provided, `1.0`, is not a valid semver version: cannot parse '1.0' as a semver
+error: the `--vers` provided, `1.0`, is not a valid semver version: cannot parse '1.0' as a semver
 
 if you want to specify semver range, add an explicit qualifier, like ^1.0
 ",

tests/testsuite/registry.rs

@@ -225,7 +225,7 @@ fn wrong_version() {
         .with_status(101)
         .with_stderr_contains(
             "\
-error: failed to select a version for the requirement `foo = \">= 1.0.0\"`
+error: failed to select a version for the requirement `foo = \">=1.0.0\"`
   candidate versions found which didn't match: 0.0.2, 0.0.1
   location searched: `[..]` index (which is replacing registry `[..]`)
 required by package `foo v0.0.1 ([..])`
@@ -240,7 +240,7 @@ required by package `foo v0.0.1 ([..])`
         .with_status(101)
         .with_stderr_contains(
             "\
-error: failed to select a version for the requirement `foo = \">= 1.0.0\"`
+error: failed to select a version for the requirement `foo = \">=1.0.0\"`
   candidate versions found which didn't match: 0.0.4, 0.0.3, 0.0.2, ...
   location searched: `[..]` index (which is replacing registry `[..]`)
 required by package `foo v0.0.1 ([..])`
@@ -540,7 +540,7 @@ fn relying_on_a_yank_is_bad() {
         .with_status(101)
         .with_stderr_contains(
             "\
-error: failed to select a version for the requirement `baz = \"= 0.0.2\"`
+error: failed to select a version for the requirement `baz = \"=0.0.2\"`
   candidate versions found which didn't match: 0.0.1
   location searched: `[..]` index (which is replacing registry `[..]`)
 required by package `bar v0.0.1`

tests/testsuite/replace.rs

@@ -549,7 +549,7 @@ fn override_wrong_name() {
 Caused by:
   no matching package for override `[..]baz:0.1.0` found
 location searched: file://[..]
-version required: = 0.1.0
+version required: =0.1.0
 ",
         )
         .run();