Merge remote-tracking branch 'origin/master' into large-path-warning

src/libexpr/primops/fetchTree.cc

@@ -137,6 +137,11 @@ static void fetchTree(
             attrs.emplace("exportIgnore", Explicit<bool>{true});
         }
 
+        // fetchTree should fetch git repos with shallow = true by default
+        if (type == "git" && !params.isFetchGit && !attrs.contains("shallow")) {
+            attrs.emplace("shallow", Explicit<bool>{true});
+        }
+
         if (!params.allowNameArgument)
             if (auto nameIter = attrs.find("name"); nameIter != attrs.end())
                 state.error<EvalError>(
@@ -320,6 +325,8 @@ static RegisterPrimOp primop_fetchTree({
 
         - `ref` (String, optional)
 
+          By default, this has no effect. This becomes relevant only once `shallow` cloning is disabled.
+
           A [Git reference](https://git-scm.com/book/en/v2/Git-Internals-Git-References), such as a branch or tag name.
 
           Default: `"HEAD"`
@@ -333,8 +340,9 @@ static RegisterPrimOp primop_fetchTree({
         - `shallow` (Bool, optional)
 
           Make a shallow clone when fetching the Git tree.
+          When this is enabled, the options `ref` and `allRefs` have no effect anymore.
 
-          Default: `false`
+          Default: `true`
 
         - `submodules` (Bool, optional)
 
@@ -344,8 +352,11 @@ static RegisterPrimOp primop_fetchTree({
 
         - `allRefs` (Bool, optional)
 
-          If set to `true`, always fetch the entire repository, even if the latest commit is still in the cache.
-          Otherwise, only the latest commit is fetched if it is not already cached.
+          By default, this has no effect. This becomes relevant only once `shallow` cloning is disabled.
+
+          Whether to fetch all references (eg. branches and tags) of the repository.
+          With this argument being true, it's possible to load a `rev` from *any* `ref`.
+          (Without setting this option, only `rev`s from the specified `ref` are supported).
 
           Default: `false`
 
@@ -599,6 +610,8 @@ static RegisterPrimOp primop_fetchGit({
 
         [Git reference]: https://git-scm.com/book/en/v2/Git-Internals-Git-References
 
+        This option has no effect once `shallow` cloning is enabled.
+
         By default, the `ref` value is prefixed with `refs/heads/`.
         As of 2.3.0, Nix will not prefix `refs/heads/` if `ref` starts with `refs/`.
 
@@ -616,13 +629,15 @@ static RegisterPrimOp primop_fetchGit({
       - `shallow` (default: `false`)
 
         Make a shallow clone when fetching the Git tree.
-
+        When this is enabled, the options `ref` and `allRefs` have no effect anymore.
       - `allRefs`
 
-        Whether to fetch all references of the repository.
-        With this argument being true, it's possible to load a `rev` from *any* `ref`
+        Whether to fetch all references (eg. branches and tags) of the repository.
+        With this argument being true, it's possible to load a `rev` from *any* `ref`.
         (by default only `rev`s from the specified `ref` are supported).
 
+        This option has no effect once `shallow` cloning is enabled.
+
       - `verifyCommit` (default: `true` if `publicKey` or `publicKeys` are provided, otherwise `false`)
 
         Whether to check `rev` for a signature matching `publicKey` or `publicKeys`.

src/libutil/hash.cc

@@ -50,21 +50,14 @@ bool Hash::operator == (const Hash & h2) const
 }
 
 
-bool Hash::operator != (const Hash & h2) const
+std::strong_ordering Hash::operator <=> (const Hash & h) const
 {
-    return !(*this == h2);
-}
-
-
-bool Hash::operator < (const Hash & h) const
-{
-    if (hashSize < h.hashSize) return true;
-    if (hashSize > h.hashSize) return false;
+    if (auto cmp = algo <=> h.algo; cmp != 0) return cmp;
+    if (auto cmp = hashSize <=> h.hashSize; cmp != 0) return cmp;
     for (unsigned int i = 0; i < hashSize; i++) {
-        if (hash[i] < h.hash[i]) return true;
-        if (hash[i] > h.hash[i]) return false;
+        if (auto cmp = hash[i] <=> h.hash[i]; cmp != 0) return cmp;
     }
-    return false;
+    return std::strong_ordering::equivalent;
 }
 
 

src/libutil/hash.hh

@@ -86,19 +86,14 @@ private:
 
 public:
     /**
-     * Check whether two hash are equal.
+     * Check whether two hashes are equal.
      */
     bool operator == (const Hash & h2) const;
 
     /**
-     * Check whether two hash are not equal.
+     * Compare how two hashes are ordered.
      */
-    bool operator != (const Hash & h2) const;
-
-    /**
-     * For sorting.
-     */
-    bool operator < (const Hash & h) const;
+    std::strong_ordering operator <=> (const Hash & h2) const;
 
     /**
      * Returns the length of a base-16 representation of this hash.

src/libutil/url.cc

@@ -171,16 +171,16 @@ std::string fixGitURL(const std::string & url)
     std::regex scpRegex("([^/]*)@(.*):(.*)");
     if (!hasPrefix(url, "/") && std::regex_match(url, scpRegex))
         return std::regex_replace(url, scpRegex, "ssh://$1@$2/$3");
-    else {
-        if (url.find("://") == std::string::npos) {
-            return (ParsedURL {
-                .scheme = "file",
-                .authority = "",
-                .path = url
-            }).to_string();
-        } else
-            return url;
+    if (hasPrefix(url, "file:"))
+        return url;
+    if (url.find("://") == std::string::npos) {
+        return (ParsedURL {
+            .scheme = "file",
+            .authority = "",
+            .path = url
+        }).to_string();
     }
+    return url;
 }
 
 // https://www.rfc-editor.org/rfc/rfc3986#section-3.1