fix(build): feature sources 在 mcpp test 下不编译 (0.0.94) (#218)

prepare_build() 把 feature 源集解析(drop + add)整段门在 `!includeDevDeps`,
`mcpp test` 走 includeDevDeps=true → 激活 feature 的 sources 从不被加回构建图。
xpkg 的 `features.X.sources` 只落进 featureSources、从不进 base sources,故
「只在 features 下声明」的包 build 正常、test 必然 undefined reference。

命中 compat.cjson `utils`、compat.eigen `eigen_blas`(dgemm_)、compat.spdlog
`compiled`。eigen_blas 的 dgemm_ 一直被记为「链进 test 二进制是 follow-up」,
定性是错的:不是链接问题,是源集解析问题。

drop 仍只在 build 模式做(test 模式需保留完整源面供 dev-dep 轨 per-test main
检测剪枝,见 e2e 79);add 改为两模式都做 + 去重(gtest 双列 glob 不会进两次)。

回归测试 e2e 100:已验证在未修复的 0.0.92 上以目标错误失败、修复后通过;
e2e 78/79(#168 gtest 回归靶子)与单测 35/35 均通过。

Author: Sunrisepeak

CHANGELOG.md

@@ -3,6 +3,28 @@
 > 本文件追踪 `mcpp-community/mcpp` 公开仓的版本演进。
 > 格式参考 [Keep a Changelog](https://keepachangelog.com/zh-CN/1.1.0/)。
 
+## [0.0.94] — 2026-07-15
+
+### 修复
+
+- **依赖包被激活 feature 的 `sources` 在 `mcpp test` 下不编译**。`prepare_build()`
+  把 feature 源集解析(drop + add)**整段**门在 `!includeDevDeps`,而 `mcpp test`
+  走 `includeDevDeps = true` → 激活 feature 的 sources **从不被加回**构建图。
+  descriptor 若把某个 glob **只**写在 `features` 下(xpkg 的 `features.X.sources`
+  只落进 `featureSources`、从不进 base `sources`),该包在 `mcpp build` 下正常、
+  在 `mcpp test` 下必然链接失败(`undefined reference`)。
+  - 命中面:`compat.cjson` 的 `utils`(`cJSONUtils_*`)、`compat.eigen` 的
+    `eigen_blas`(`dgemm_`)、`compat.spdlog` 的 `compiled`。
+  - **`eigen_blas` 的 `dgemm_` 一直被记为「把 feature 编出的依赖目标链进 test
+    二进制是 follow-up」——定性是错的**:不是链接问题,是**源集解析**问题。
+  - 修复:**drop 仍只在 build 模式做**(`mcpp test` 需要保留完整源面,让 dev-dep
+    轨的 per-test main 检测看得见 `gtest_main.cc` 并逐 test 剪枝——见
+    `tests/e2e/79_gtest_regular_dep_feature_main.sh`);**add 改为两模式都做**,
+    并**去重**,使 gtest 那种 base/feature 双列的 glob 不会进两次。
+  - 回归测试:`tests/e2e/100_feature_sources_test_mode.sh`(cjson `utils` 在
+    `mcpp test` 下必须编译并链接;`mcpp build` 仍正常;不请求 feature 时 gated
+    源仍被排除)。
+
 ## [0.0.93] — 2026-07-15
 
 ### 变更(命名统一,全部旧拼写永久兼容)

mcpp.toml

@@ -1,6 +1,6 @@
 [package]
 name        = "mcpp"
-version     = "0.0.93"
+version     = "0.0.94"
 description = "Modern C++ build & package management tool"
 license     = "Apache-2.0"
 authors     = ["mcpp-community"]

src/build/prepare.cppm

@@ -2479,32 +2479,47 @@ prepare_build(bool print_fingerprint,
                     }
             }
             // Feature-gated sources (e.g. gtest's gtest_main.cc behind "main"):
-            // drop EVERY feature-listed glob from the default build, then re-add
-            // only the ones whose feature is active. Runs even when no feature is
-            // active, so a gated source is excluded by default.
+            // drop EVERY feature-listed glob from the default build, then add
+            // back only the ones whose feature is active. Runs even when no
+            // feature is active, so a gated source is excluded by default.
             //
-            // ONLY in build mode (!includeDevDeps). `mcpp test` (includeDevDeps)
-            // keeps the full surface so the dev-dependency track's per-test main
-            // detection (run_tests / make_plan) still sees gtest_main.cc and
-            // prunes it per test — the two tracks stay decoupled. Combined with
-            // the descriptor keeping gtest_main.cc in base `sources` too, this
-            // means test mode is unaffected.
+            // The DROP is build-mode only (!includeDevDeps). `mcpp test`
+            // (includeDevDeps) keeps the full surface so the dev-dependency
+            // track's per-test main detection (run_tests / make_plan) still sees
+            // gtest_main.cc and prunes it per test — the two tracks stay
+            // decoupled; gtest's descriptor keeps gtest_main.cc in base `sources`
+            // too, so skipping the drop leaves it visible.
+            //
+            // The ADD runs in BOTH modes. A descriptor may list a glob ONLY under
+            // `features` and never in base `sources` (xpkg's `features.X.sources`
+            // lands in featureSources alone — compat.spdlog's `compiled`,
+            // compat.cjson's `utils`, compat.eigen's `eigen_blas`). Gating the add
+            // on !includeDevDeps meant those sources were never compiled under
+            // `mcpp test` → link-time `undefined reference` (the eigen_blas
+            // `dgemm_` failure, long misread as a linking follow-up: it was
+            // source-set resolution, not linking). Add is dedup'd so gtest's
+            // doubly-listed gtest_main.cc cannot land twice.
             auto& bc = pkg.manifest.buildConfig;
-            if (!includeDevDeps && !bc.featureSources.empty()) {
-                std::set<std::string> gated;
-                for (auto& [f, globs] : bc.featureSources)
-                    for (auto& g : globs) gated.insert(g);
-                auto drop = [&](std::vector<std::string>& v) {
-                    std::erase_if(v, [&](const std::string& s) { return gated.contains(s); });
-                };
-                drop(bc.sources);
-                drop(pkg.manifest.modules.sources);
+            if (!bc.featureSources.empty()) {
+                if (!includeDevDeps) {
+                    std::set<std::string> gated;
+                    for (auto& [f, globs] : bc.featureSources)
+                        for (auto& g : globs) gated.insert(g);
+                    auto drop = [&](std::vector<std::string>& v) {
+                        std::erase_if(v, [&](const std::string& s) { return gated.contains(s); });
+                    };
+                    drop(bc.sources);
+                    drop(pkg.manifest.modules.sources);
+                }
                 std::set<std::string> activeSet(active.begin(), active.end());
+                auto add = [](std::vector<std::string>& v, const std::string& g) {
+                    if (std::ranges::find(v, g) == v.end()) v.push_back(g);
+                };
                 for (auto& [f, globs] : bc.featureSources) {
                     if (!activeSet.contains(f)) continue;
                     for (auto& g : globs) {
-                        bc.sources.push_back(g);
-                        pkg.manifest.modules.sources.push_back(g);
+                        add(bc.sources, g);
+                        add(pkg.manifest.modules.sources, g);
                     }
                 }
             }

src/toolchain/fingerprint.cppm

@@ -18,7 +18,7 @@ import mcpp.toolchain.detect;
 
 export namespace mcpp::toolchain {
 
-inline constexpr std::string_view MCPP_VERSION = "0.0.93";
+inline constexpr std::string_view MCPP_VERSION = "0.0.94";
 
 struct FingerprintInputs {
     Toolchain                       toolchain;

tests/e2e/100_feature_sources_test_mode.sh

@@ -0,0 +1,97 @@
+#!/usr/bin/env bash
+# requires:
+# 100_feature_sources_test_mode.sh — a dependency's feature-gated `sources` must
+# be compiled under `mcpp test`, not just `mcpp build`.
+#
+# Regression: prepare_build() gated the whole feature-source resolution (drop +
+# add) on `!includeDevDeps`, so `mcpp test` never added an active feature's
+# sources. Descriptors that list a glob ONLY under `features` (xpkg's
+# `features.X.sources` never lands in base `sources`) therefore compiled fine
+# under `mcpp build` but failed to link under `mcpp test` with `undefined
+# reference` — compat.cjson's `utils`, compat.spdlog's `compiled`, and
+# compat.eigen's `eigen_blas` all hit this. The drop stays build-mode only (see
+# 79_gtest_regular_dep_feature_main.sh); the add now runs in both modes.
+#
+# compat.cjson is the vehicle: plain C, small, and `utils` (cJSON_Utils.c) is
+# feature-gated with no other dependency.
+set -e
+
+TMP=$(mktemp -d)
+trap "rm -rf $TMP" EXIT
+
+cd "$TMP"
+"$MCPP" new app > /dev/null
+cd app
+rm -f src/main.cpp
+mkdir -p tests
+
+cat > mcpp.toml <<'EOF'
+[package]
+name = "app"
+version = "0.1.0"
+
+[dependencies]
+cjson = { version = "1.7.19", features = ["utils"] }
+EOF
+
+# Calls into BOTH the base sources (cJSON.c) and the feature-gated ones
+# (cJSON_Utils.c) — a link failure on either fails the test.
+cat > tests/t.cpp <<'EOF'
+#include <cJSON.h>
+#include <cJSON_Utils.h>
+int main() {
+    cJSON* root = cJSON_Parse("{\"a\":1}");
+    if (!root) return 1;
+    char* p = cJSONUtils_FindPointerFromObjectTo(root, root);
+    int ok = (p != 0);
+    cJSON_Delete(root);
+    return ok ? 0 : 1;
+}
+EOF
+
+# (1) THE REGRESSION: `mcpp test` must compile the feature's sources and link.
+"$MCPP" test > /dev/null 2>&1 || {
+    echo "FAIL: feature-gated sources not compiled under \`mcpp test\`"
+    "$MCPP" test 2>&1 | tail -5
+    exit 1
+}
+nj=$(find target -name build.ninja | xargs ls -t 2>/dev/null | head -1)
+grep -q 'cJSON_Utils' "$nj" || {
+    echo "FAIL: cJSON_Utils.c absent from the test-mode build graph"; exit 1
+}
+
+# (2) `mcpp build` keeps working (the path that was always correct).
+cat > src/main.cpp <<'EOF'
+#include <cJSON.h>
+#include <cJSON_Utils.h>
+int main() {
+    cJSON* root = cJSON_Parse("{\"a\":1}");
+    char* p = cJSONUtils_FindPointerFromObjectTo(root, root);
+    (void)p; cJSON_Delete(root); return 0;
+}
+EOF
+"$MCPP" build > /dev/null || { echo "FAIL: build with feature sources failed"; exit 1; }
+nj=$(find target -name build.ninja | xargs ls -t 2>/dev/null | head -1)
+grep -q 'cJSON_Utils' "$nj" || { echo "FAIL: cJSON_Utils.c absent from build graph"; exit 1; }
+
+# (3) The drop still works: without the feature, the gated source stays OUT of a
+#     `mcpp build` graph (guards against "add everything unconditionally").
+cat > mcpp.toml <<'EOF'
+[package]
+name = "app"
+version = "0.1.0"
+
+[dependencies]
+cjson = "1.7.19"
+EOF
+cat > src/main.cpp <<'EOF'
+#include <cJSON.h>
+int main() { cJSON* r = cJSON_Parse("{\"a\":1}"); cJSON_Delete(r); return 0; }
+EOF
+"$MCPP" build > /dev/null || { echo "FAIL: default (no feature) build failed"; exit 1; }
+nj=$(find target -name build.ninja | xargs ls -t 2>/dev/null | head -1)
+if grep -q 'cJSON_Utils' "$nj"; then
+    echo "FAIL: cJSON_Utils.c compiled without the \`utils\` feature"; exit 1
+fi
+
+echo "OK"