1 files changed, 109 insertions, 115 deletions

diff --git a/src/libfetchers/mercurial.cc b/src/libfetchers/mercurial.cc
index 2e0d4bf4d..c48cb6fd1 100644
--- a/src/libfetchers/mercurial.cc
+++ b/src/libfetchers/mercurial.cc
@@ -10,76 +10,124 @@ using namespace std::string_literals;
 
 namespace nix::fetchers {
 
-struct MercurialInput : Input
+struct MercurialInputScheme : InputScheme
 {
-    ParsedURL url;
-    std::optional<std::string> ref;
-    std::optional<Hash> rev;
+    std::optional<Input> inputFromURL(const ParsedURL & url) override
+    {
+        if (url.scheme != "hg+http" &&
+            url.scheme != "hg+https" &&
+            url.scheme != "hg+ssh" &&
+            url.scheme != "hg+file") return {};
 
-    MercurialInput(const ParsedURL & url) : url(url)
-    { }
+        auto url2(url);
+        url2.scheme = std::string(url2.scheme, 3);
+        url2.query.clear();
+
+        Attrs attrs;
+        attrs.emplace("type", "hg");
 
-    std::string type() const override { return "hg"; }
+        for (auto &[name, value] : url.query) {
+            if (name == "rev" || name == "ref")
+                attrs.emplace(name, value);
+            else
+                url2.query.emplace(name, value);
+        }
+
+        attrs.emplace("url", url2.to_string());
+
+        return inputFromAttrs(attrs);
+    }
 
-    bool operator ==(const Input & other) const override
+    std::optional<Input> inputFromAttrs(const Attrs & attrs) override
     {
-        auto other2 = dynamic_cast<const MercurialInput *>(&other);
-        return
-            other2
-            && url == other2->url
-            && rev == other2->rev
-            && ref == other2->ref;
+        if (maybeGetStrAttr(attrs, "type") != "hg") return {};
+
+        for (auto & [name, value] : attrs)
+            if (name != "type" && name != "url" && name != "ref" && name != "rev" && name != "revCount" && name != "narHash")
+                throw Error("unsupported Mercurial input attribute '%s'", name);
+
+        parseURL(getStrAttr(attrs, "url"));
+
+        if (auto ref = maybeGetStrAttr(attrs, "ref")) {
+            if (!std::regex_match(*ref, refRegex))
+                throw BadURL("invalid Mercurial branch/tag name '%s'", *ref);
+        }
+
+        Input input;
+        input.attrs = attrs;
+        return input;
     }
 
-    bool isImmutable() const override
+    ParsedURL toURL(const Input & input) override
     {
-        return (bool) rev || narHash;
+        auto url = parseURL(getStrAttr(input.attrs, "url"));
+        url.scheme = "hg+" + url.scheme;
+        if (auto rev = input.getRev()) url.query.insert_or_assign("rev", rev->gitRev());
+        if (auto ref = input.getRef()) url.query.insert_or_assign("ref", *ref);
+        return url;
     }
 
-    std::optional<std::string> getRef() const override { return ref; }
+    bool hasAllInfo(const Input & input) override
+    {
+        // FIXME: ugly, need to distinguish between dirty and clean
+        // default trees.
+        return input.getRef() == "default" || maybeGetIntAttr(input.attrs, "revCount");
+    }
 
-    std::optional<Hash> getRev() const override { return rev; }
+    Input applyOverrides(
+        const Input & input,
+        std::optional<std::string> ref,
+        std::optional<Hash> rev) override
+    {
+        auto res(input);
+        if (rev) res.attrs.insert_or_assign("rev", rev->gitRev());
+        if (ref) res.attrs.insert_or_assign("ref", *ref);
+        return res;
+    }
 
-    ParsedURL toURL() const override
+    std::optional<Path> getSourcePath(const Input & input) override
     {
-        ParsedURL url2(url);
-        url2.scheme = "hg+" + url2.scheme;
-        if (rev) url2.query.insert_or_assign("rev", rev->gitRev());
-        if (ref) url2.query.insert_or_assign("ref", *ref);
-        return url;
+        auto url = parseURL(getStrAttr(input.attrs, "url"));
+        if (url.scheme == "file" && !input.getRef() && !input.getRev())
+            return url.path;
+        return {};
     }
 
-    Attrs toAttrsInternal() const override
+    void markChangedFile(const Input & input, std::string_view file, std::optional<std::string> commitMsg) override
     {
-        Attrs attrs;
-        attrs.emplace("url", url.to_string());
-        if (ref)
-            attrs.emplace("ref", *ref);
-        if (rev)
-            attrs.emplace("rev", rev->gitRev());
-        return attrs;
+        auto sourcePath = getSourcePath(input);
+        assert(sourcePath);
+
+        // FIXME: shut up if file is already tracked.
+        runProgram("hg", true,
+            { "add", *sourcePath + "/" + std::string(file) });
+
+        if (commitMsg)
+            runProgram("hg", true,
+                { "commit", *sourcePath + "/" + std::string(file), "-m", *commitMsg });
     }
 
-    std::pair<bool, std::string> getActualUrl() const
+    std::pair<bool, std::string> getActualUrl(const Input & input) const
     {
+        auto url = parseURL(getStrAttr(input.attrs, "url"));
         bool isLocal = url.scheme == "file";
         return {isLocal, isLocal ? url.path : url.base};
     }
 
-    std::pair<Tree, std::shared_ptr<const Input>> fetchTreeInternal(nix::ref<Store> store) const override
+    std::pair<Tree, Input> fetch(ref<Store> store, const Input & _input) override
     {
         auto name = "source";
 
-        auto input = std::make_shared<MercurialInput>(*this);
+        Input input(_input);
 
-        auto [isLocal, actualUrl_] = getActualUrl();
+        auto [isLocal, actualUrl_] = getActualUrl(input);
         auto actualUrl = actualUrl_; // work around clang bug
 
         // FIXME: return lastModified.
 
         // FIXME: don't clone local repositories.
 
-        if (!input->ref && !input->rev && isLocal && pathExists(actualUrl + "/.hg")) {
+        if (!input.getRef() && !input.getRev() && isLocal && pathExists(actualUrl + "/.hg")) {
 
             bool clean = runProgram("hg", true, { "status", "-R", actualUrl, "--modified", "--added", "--removed" }) == "";
 
@@ -94,7 +142,7 @@ struct MercurialInput : Input
                 if (settings.warnDirty)
                     warn("Mercurial tree '%s' is unclean", actualUrl);
 
-                input->ref = chomp(runProgram("hg", true, { "branch", "-R", actualUrl }));
+                input.attrs.insert_or_assign("ref", chomp(runProgram("hg", true, { "branch", "-R", actualUrl })));
 
                 auto files = tokenizeString<std::set<std::string>>(
                     runProgram("hg", true, { "status", "-R", actualUrl, "--clean", "--modified", "--added", "--no-status", "--print0" }), "\0"s);
@@ -116,60 +164,54 @@ struct MercurialInput : Input
 
                 auto storePath = store->addToStore("source", actualUrl, FileIngestionMethod::Recursive, htSHA256, filter);
 
-                return {Tree {
-                    .actualPath = store->printStorePath(storePath),
-                    .storePath = std::move(storePath),
-                }, input};
+                return {
+                    Tree(store->printStorePath(storePath), std::move(storePath)),
+                    input
+                };
             }
         }
 
-        if (!input->ref) input->ref = "default";
+        if (!input.getRef()) input.attrs.insert_or_assign("ref", "default");
 
         auto getImmutableAttrs = [&]()
         {
             return Attrs({
                 {"type", "hg"},
                 {"name", name},
-                {"rev", input->rev->gitRev()},
+                {"rev", input.getRev()->gitRev()},
             });
         };
 
         auto makeResult = [&](const Attrs & infoAttrs, StorePath && storePath)
-            -> std::pair<Tree, std::shared_ptr<const Input>>
+            -> std::pair<Tree, Input>
         {
-            assert(input->rev);
-            assert(!rev || rev == input->rev);
+            assert(input.getRev());
+            assert(!_input.getRev() || _input.getRev() == input.getRev());
+            input.attrs.insert_or_assign("revCount", getIntAttr(infoAttrs, "revCount"));
             return {
-                Tree{
-                    .actualPath = store->toRealPath(storePath),
-                    .storePath = std::move(storePath),
-                    .info = TreeInfo {
-                        .revCount = getIntAttr(infoAttrs, "revCount"),
-                    },
-                },
+                Tree(store->toRealPath(storePath), std::move(storePath)),
                 input
             };
         };
 
-        if (input->rev) {
+        if (input.getRev()) {
             if (auto res = getCache()->lookup(store, getImmutableAttrs()))
                 return makeResult(res->first, std::move(res->second));
         }
 
-        assert(input->rev || input->ref);
-        auto revOrRef = input->rev ? input->rev->gitRev() : *input->ref;
+        auto revOrRef = input.getRev() ? input.getRev()->gitRev() : *input.getRef();
 
         Attrs mutableAttrs({
             {"type", "hg"},
             {"name", name},
             {"url", actualUrl},
-            {"ref", *input->ref},
+            {"ref", *input.getRef()},
         });
 
         if (auto res = getCache()->lookup(store, mutableAttrs)) {
             auto rev2 = Hash(getStrAttr(res->first, "rev"), htSHA1);
-            if (!rev || rev == rev2) {
-                input->rev = rev2;
+            if (!input.getRev() || input.getRev() == rev2) {
+                input.attrs.insert_or_assign("rev", rev2.gitRev());
                 return makeResult(res->first, std::move(res->second));
             }
         }
@@ -178,10 +220,10 @@ struct MercurialInput : Input
 
         /* If this is a commit hash that we already have, we don't
            have to pull again. */
-        if (!(input->rev
+        if (!(input.getRev()
                 && pathExists(cacheDir)
                 && runProgram(
-                    RunOptions("hg", { "log", "-R", cacheDir, "-r", input->rev->gitRev(), "--template", "1" })
+                    RunOptions("hg", { "log", "-R", cacheDir, "-r", input.getRev()->gitRev(), "--template", "1" })
                     .killStderr(true)).second == "1"))
         {
             Activity act(*logger, lvlTalkative, actUnknown, fmt("fetching Mercurial repository '%s'", actualUrl));
@@ -210,9 +252,9 @@ struct MercurialInput : Input
             runProgram("hg", true, { "log", "-R", cacheDir, "-r", revOrRef, "--template", "{node} {rev} {branch}" }));
         assert(tokens.size() == 3);
 
-        input->rev = Hash(tokens[0], htSHA1);
+        input.attrs.insert_or_assign("rev", Hash(tokens[0], htSHA1).gitRev());
         auto revCount = std::stoull(tokens[1]);
-        input->ref = tokens[2];
+        input.attrs.insert_or_assign("ref", tokens[2]);
 
         if (auto res = getCache()->lookup(store, getImmutableAttrs()))
             return makeResult(res->first, std::move(res->second));
@@ -220,18 +262,18 @@ struct MercurialInput : Input
         Path tmpDir = createTempDir();
         AutoDelete delTmpDir(tmpDir, true);
 
-        runProgram("hg", true, { "archive", "-R", cacheDir, "-r", input->rev->gitRev(), tmpDir });
+        runProgram("hg", true, { "archive", "-R", cacheDir, "-r", input.getRev()->gitRev(), tmpDir });
 
         deletePath(tmpDir + "/.hg_archival.txt");
 
         auto storePath = store->addToStore(name, tmpDir);
 
         Attrs infoAttrs({
-            {"rev", input->rev->gitRev()},
+            {"rev", input.getRev()->gitRev()},
             {"revCount", (int64_t) revCount},
         });
 
-        if (!this->rev)
+        if (!_input.getRev())
             getCache()->add(
                 store,
                 mutableAttrs,
@@ -250,54 +292,6 @@ struct MercurialInput : Input
     }
 };
 
-struct MercurialInputScheme : InputScheme
-{
-    std::unique_ptr<Input> inputFromURL(const ParsedURL & url) override
-    {
-        if (url.scheme != "hg+http" &&
-            url.scheme != "hg+https" &&
-            url.scheme != "hg+ssh" &&
-            url.scheme != "hg+file") return nullptr;
-
-        auto url2(url);
-        url2.scheme = std::string(url2.scheme, 3);
-        url2.query.clear();
-
-        Attrs attrs;
-        attrs.emplace("type", "hg");
-
-        for (auto &[name, value] : url.query) {
-            if (name == "rev" || name == "ref")
-                attrs.emplace(name, value);
-            else
-                url2.query.emplace(name, value);
-        }
-
-        attrs.emplace("url", url2.to_string());
-
-        return inputFromAttrs(attrs);
-    }
-
-    std::unique_ptr<Input> inputFromAttrs(const Attrs & attrs) override
-    {
-        if (maybeGetStrAttr(attrs, "type") != "hg") return {};
-
-        for (auto & [name, value] : attrs)
-            if (name != "type" && name != "url" && name != "ref" && name != "rev")
-                throw Error("unsupported Mercurial input attribute '%s'", name);
-
-        auto input = std::make_unique<MercurialInput>(parseURL(getStrAttr(attrs, "url")));
-        if (auto ref = maybeGetStrAttr(attrs, "ref")) {
-            if (!std::regex_match(*ref, refRegex))
-                throw BadURL("invalid Mercurial branch/tag name '%s'", *ref);
-            input->ref = *ref;
-        }
-        if (auto rev = maybeGetStrAttr(attrs, "rev"))
-            input->rev = Hash(*rev, htSHA1);
-        return input;
-    }
-};
-
 static auto r1 = OnStartup([] { registerInputScheme(std::make_unique<MercurialInputScheme>()); });
 
 }