Import the results of other test frameworks

Tests Catch3 does not run had no history, flaky detection or quarantine.
--import=FILE reads a report instead of running tests and sends it through
the analysis, history and reports of a run: JUnit with Surefire's reruns,
xUnit.net v2, TRX, TAP 12 to 14, CTRF, Catch3's own --json report and
catch3-results, a small JSON Lines format for tools with none of these.

Results that share an identifier are attempts at one test, so a report of a
rerun gives a flaky test. --import-revision says what was tested: a verdict
that changes on one revision also counts as flaky. --import-name keeps the
results in a history of their own, which --analytics reads too. A TAP stream
that ends early fails instead of reading as a run that passed.

The amalgamation script now accepts a relative include of the third-party
wrappers, because pugixml is included from a second directory.

1 files changed, 305 insertions, 0 deletions

diff --git a/src/Progmasoft/Runner/ResultImport.cpp b/src/Progmasoft/Runner/ResultImport.cpp
new file mode 100644
index 00000000..10a9c5a8
--- /dev/null
+++ b/src/Progmasoft/Runner/ResultImport.cpp
@@ -0,0 +1,305 @@
+// Copyright (c) 2026 Progmasoft.
+// SPDX-License-Identifier: MPL-2.0 WITH AdditionRef-Progmasoft-Exception-2.0
+#include <Progmasoft/Runner/History.hpp>
+#include <Progmasoft/Runner/Json.hpp>
+#include <Progmasoft/Runner/ResultImport.hpp>
+#include <algorithm>
+#include <cctype>
+#include <cmath>
+#include <iterator>
+#include <map>
+#include <utility>
+
+namespace Progmasoft::Catch3::Runner
+{
+    std::string_view
+    ImportTrim(std::string_view text)
+    {
+        const auto blank = [](char character) {
+            return std::isspace(static_cast<unsigned char>(character)) != 0;
+        };
+        while (!text.empty() && blank(text.front()))
+        {
+            text.remove_prefix(1);
+        }
+        while (!text.empty() && blank(text.back()))
+        {
+            text.remove_suffix(1);
+        }
+        return text;
+    }
+
+    bool
+    ImportStartsWith(std::string_view text, std::string_view prefix)
+    {
+        return text.substr(0, prefix.size()) == prefix;
+    }
+
+    std::vector<std::string_view>
+    ImportLines(std::string_view text)
+    {
+        std::vector<std::string_view> lines;
+        while (!text.empty())
+        {
+            const auto end = text.find('\n');
+            auto line = text.substr(0, end);
+            if (!line.empty() && line.back() == '\r')
+            {
+                line.remove_suffix(1);
+            }
+            lines.push_back(line);
+            if (end == std::string_view::npos)
+            {
+                break;
+            }
+            text.remove_prefix(end + 1);
+        }
+        return lines;
+    }
+
+    namespace
+    {
+        namespace ImportText
+        {
+            /// Without a byte order mark and the white space before the
+            /// first character that counts.
+            std::string_view
+            Contents(std::string_view text)
+            {
+                if (ImportStartsWith(text, "\xEF\xBB\xBF"))
+                {
+                    text.remove_prefix(3);
+                }
+                return ImportTrim(text);
+            }
+
+            /// The name of the root element of an XML document.
+            std::string_view
+            RootElement(std::string_view text)
+            {
+                while (!text.empty())
+                {
+                    const auto open = text.find('<');
+                    if (open == std::string_view::npos
+                        || open + 1 >= text.size())
+                    {
+                        return {};
+                    }
+                    text.remove_prefix(open + 1);
+                    if (text.front() == '?' || text.front() == '!')
+                    {
+                        const auto close = text.find('>');
+                        if (close == std::string_view::npos)
+                        {
+                            return {};
+                        }
+                        text.remove_prefix(close + 1);
+                        continue;
+                    }
+                    return text.substr(0, text.find_first_of(" \t\r\n/>"));
+                }
+                return {};
+            }
+        } // namespace ImportText
+    } // namespace
+
+    std::optional<ImportFormat>
+    DetectImportFormat(std::string_view text)
+    {
+        const std::string_view contents = ImportText::Contents(text);
+        if (contents.empty())
+        {
+            return std::nullopt;
+        }
+        if (contents.front() == '<')
+        {
+            const std::string_view root = ImportText::RootElement(contents);
+            if (root == "testsuites" || root == "testsuite")
+            {
+                return ImportFormat::kJUnit;
+            }
+            if (root == "assemblies" || root == "assembly")
+            {
+                return ImportFormat::kXUnit;
+            }
+            if (root == "TestRun")
+            {
+                return ImportFormat::kTrx;
+            }
+            return std::nullopt;
+        }
+        if (contents.front() == '{')
+        {
+            auto whole = ParseJson(contents);
+            if (!whole)
+            {
+                // JSON Lines: the first line says what the others are.
+                whole = ParseJson(contents.substr(0, contents.find('\n')));
+            }
+            return whole ? ImportJsonFormat(*whole) : std::nullopt;
+        }
+        for (const auto raw : ImportLines(contents))
+        {
+            const std::string_view line = ImportTrim(raw);
+            if (line.empty() || line.front() == '#')
+            {
+                continue;
+            }
+            if (ImportStartsWith(line, "TAP version")
+                || ImportStartsWith(line, "1..") || IsTapTestLine(line))
+            {
+                return ImportFormat::kTap;
+            }
+            break;
+        }
+        return std::nullopt;
+    }
+
+    Expected<std::vector<TestResult>>
+    ParseImport(std::string_view text, ImportFormat format)
+    {
+        const std::string_view contents = ImportText::Contents(text);
+        switch (format)
+        {
+            case ImportFormat::kAuto:
+                break;
+            case ImportFormat::kCatch3:
+                return ParseCatch3Report(contents);
+            case ImportFormat::kJUnit:
+                return ParseJUnit(contents);
+            case ImportFormat::kXUnit:
+                return ParseXUnit(contents);
+            case ImportFormat::kTrx:
+                return ParseTrx(contents);
+            case ImportFormat::kTap:
+                return ParseTap(contents);
+            case ImportFormat::kCtrf:
+                return ParseCtrf(contents);
+        }
+        const auto detected = DetectImportFormat(contents);
+        if (!detected)
+        {
+            return Error{ "its format is not one Catch3 knows; "
+                          "--import-format names it" };
+        }
+        return ParseImport(contents, *detected);
+    }
+
+    std::vector<TestResult>
+    MergeImported(std::vector<TestResult> results)
+    {
+        std::vector<TestResult> tests;
+        std::map<std::string, std::size_t> positions;
+        for (auto &result : results)
+        {
+            if (result.id.empty())
+            {
+                result.id = History::KeyOf(result);
+            }
+            const auto [position, added]
+                = positions.emplace(result.id, tests.size());
+            if (added)
+            {
+                tests.push_back(std::move(result));
+                continue;
+            }
+            TestResult &test = tests[position->second];
+            test.flaky = test.flaky || result.flaky;
+            std::move(result.attempts.begin(),
+                      result.attempts.end(),
+                      std::back_inserter(test.attempts));
+        }
+        for (auto &test : tests)
+        {
+            std::size_t passes = 0;
+            std::size_t failures = 0;
+            for (std::size_t index = 0; index < test.attempts.size(); ++index)
+            {
+                Attempt &attempt = test.attempts[index];
+                attempt.number = index + 1;
+                passes += attempt.outcome == Outcome::kPassed ? 1 : 0;
+                failures += IsFailure(attempt.outcome) ? 1 : 0;
+            }
+            if (test.attempts.empty())
+            {
+                continue;
+            }
+            test.outcome = test.attempts.back().outcome;
+            test.category = test.attempts.back().category;
+            if (passes > 0 && failures > 0)
+            {
+                test.outcome = Outcome::kPassed;
+                test.category = FailureCategory::kNone;
+                test.flaky = true;
+                test.analysis.push_back(
+                    "flaky: failed " + std::to_string(failures) + " of "
+                    + std::to_string(test.attempts.size()) + " attempts");
+            }
+        }
+        return tests;
+    }
+
+    TestResult
+    ImportedTest(std::string name, std::string className)
+    {
+        TestResult test;
+        test.name = std::move(name);
+        test.className = std::move(className);
+        test.id = History::KeyOf(test);
+        return test;
+    }
+
+    Attempt
+    ImportedAttempt(Outcome outcome,
+                    std::int64_t durationMicroseconds,
+                    std::string message,
+                    std::string details,
+                    FailureCategory category)
+    {
+        Attempt attempt;
+        attempt.outcome = outcome;
+        attempt.durationMicroseconds
+            = std::max<std::int64_t>(durationMicroseconds, 0);
+        if (outcome == Outcome::kSkipped)
+        {
+            attempt.standardOutput = std::move(message);
+            return attempt;
+        }
+        if (outcome != Outcome::kFailedAsExpected && !IsFailure(outcome))
+        {
+            return attempt;
+        }
+        if (category == FailureCategory::kNone)
+        {
+            category = outcome == Outcome::kCrashed ? FailureCategory::kCrash
+                       : outcome == Outcome::kTimedOut
+                           ? FailureCategory::kTimeout
+                           : FailureCategory::kAssertion;
+        }
+        if (message.empty())
+        {
+            message = details.substr(0, details.find('\n'));
+        }
+        attempt.category = category;
+        attempt.assertionsFailed = 1;
+        AssertionRecord assertion;
+        assertion.message = std::move(message);
+        assertion.expansion = std::move(details);
+        assertion.category = category;
+        assertion.allowed = outcome == Outcome::kFailedAsExpected;
+        attempt.assertions.push_back(std::move(assertion));
+        return attempt;
+    }
+
+    std::int64_t
+    ImportedMicroseconds(double seconds)
+    {
+        // About thirty years; a longer duration is not a duration.
+        constexpr double kLongest = 1e9;
+        if (!std::isfinite(seconds) || seconds <= 0.0 || seconds > kLongest)
+        {
+            return 0;
+        }
+        return static_cast<std::int64_t>(std::llround(seconds * 1e6));
+    }
+} // namespace Progmasoft::Catch3::Runner