[WIP] - Inform when there is no minor version

README.md

@@ -58,19 +58,19 @@ as part of your CI pipeline. For example in a GitHub action, note the use of
 jobs:
   roave-backwards-compatibility-check:
     name: Roave Backwards Compatibility Check
-      runs-on: ubuntu-latest
-      steps:
-        - uses: actions/checkout@v2
-          with:
-            fetch-depth: 0
-        - name: "Install PHP"
-          uses: shivammathur/setup-php@v2
-          with:
-            php-version: "8.0"
-        - name: "Install dependencies"
-          run: "composer install"
-        - name: "Check for BC breaks"
-          run: "vendor/bin/roave-backward-compatibility-check"
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+      - name: "Install PHP"
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: "8.0"
+      - name: "Install dependencies"
+        run: "composer install"
+      - name: "Check for BC breaks"
+        run: "vendor/bin/roave-backward-compatibility-check"
 ```
 
 #### Nyholm Github Action

src/Command/AssertBackwardsCompatible.php

@@ -21,8 +21,8 @@
 use Roave\BackwardCompatibility\Git\ParseRevision;
 use Roave\BackwardCompatibility\Git\PerformCheckoutOfRevision;
 use Roave\BackwardCompatibility\Git\PickVersionFromVersionCollection;
-use Roave\BackwardCompatibility\Git\Revision;
 use Roave\BackwardCompatibility\LocateDependencies\LocateDependencies;
+use Roave\BackwardCompatibility\VersionConstraint\StableVersionConstraint;
 use Roave\BetterReflection\SourceLocator\Type\AggregateSourceLocator;
 use Symfony\Component\Console\Command\Command;
 use Symfony\Component\Console\Exception\InvalidArgumentException;
@@ -115,9 +115,27 @@ public function execute(InputInterface $input, OutputInterface $output): int
         // @todo fix flaky assumption about the path of the source repo...
         $sourceRepo = CheckedOutRepository::fromPath(Env\current_dir());
 
-        $fromRevision = $input->getOption('from') !== null
-            ? $this->parseRevisionFromInput($input, $sourceRepo)
-            : $this->determineFromRevisionFromRepository($sourceRepo, $stdErr);
+        if ($input->getOption('from') !== null) {
+            $maybeRevision = Type\string()->coerce($input->getOption('from'));
+        } else {
+            $versions = $this->getVersions->fromRepository($sourceRepo);
+
+            Psl\invariant(Iter\count($versions) >= 1, 'Could not detect any released versions for the given repository');
+
+            $stableVersions = $versions->matching(new StableVersionConstraint());
+
+            if ($stableVersions->isEmpty()) {
+                $stdErr->writeln(Str\format('Your library does not have any stable versions. Therefore cannot have BC breaks.'));
+
+                return Command::SUCCESS;
+            }
+
+            $maybeRevision = $this->pickFromVersion->forVersions($versions)->toString();
+
+            $stdErr->writeln(Str\format('Detected last minor version: %s', $maybeRevision));
+        }
+
+        $fromRevision = $this->parseRevision->fromStringForRepository($maybeRevision, $sourceRepo);
 
         $to = Type\string()->coerce($input->getOption('to'));
 
@@ -187,30 +205,4 @@ private function printOutcomeAndExit(Changes $changes, OutputInterface $stdErr):
 
         return $hasBcBreaks ? 3 : 0;
     }
-
-    /** @throws InvalidArgumentException */
-    private function parseRevisionFromInput(InputInterface $input, CheckedOutRepository $repository): Revision
-    {
-        $from = Type\string()->coerce($input->getOption('from'));
-
-        return $this->parseRevision->fromStringForRepository($from, $repository);
-    }
-
-    private function determineFromRevisionFromRepository(
-        CheckedOutRepository $repository,
-        OutputInterface $output,
-    ): Revision {
-        $versions = $this->getVersions->fromRepository($repository);
-
-        Psl\invariant(Iter\count($versions) >= 1, 'Could not detect any released versions for the given repository');
-
-        $versionString = $this->pickFromVersion->forVersions($versions)->toString();
-
-        $output->writeln(Str\format('Detected last minor version: %s', $versionString));
-
-        return $this->parseRevision->fromStringForRepository(
-            $versionString,
-            $repository,
-        );
-    }
 }

src/Git/PickLastMinorVersionFromCollection.php

@@ -6,8 +6,8 @@
 
 use Psl;
 use Psl\Type;
+use Roave\BackwardCompatibility\VersionConstraint\StableVersionConstraint;
 use Version\Comparison\Constraint\CompositeConstraint;
-use Version\Comparison\Constraint\Constraint;
 use Version\Comparison\Constraint\OperationConstraint;
 use Version\Version;
 use Version\VersionCollection;
@@ -18,12 +18,7 @@ public function forVersions(VersionCollection $versionsCollection): Version
     {
         Psl\invariant(! $versionsCollection->isEmpty(), 'Cannot determine latest minor version from an empty collection');
 
-        $stableVersions = $versionsCollection->matching(new class implements Constraint {
-            public function assert(Version $version): bool
-            {
-                return ! $version->isPreRelease();
-            }
-        });
+        $stableVersions = $versionsCollection->matching(new StableVersionConstraint());
 
         $versionsSortedDescending = $stableVersions->sortedDescending();
 

src/VersionConstraint/StableVersionConstraint.php

@@ -0,0 +1,16 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Roave\BackwardCompatibility\VersionConstraint;
+
+use Version\Comparison\Constraint\Constraint;
+use Version\Version;
+
+final class StableVersionConstraint implements Constraint
+{
+    public function assert(Version $version): bool
+    {
+        return ! $version->isPreRelease();
+    }
+}

test/unit/VersionConstraint/StableVersionConstraintTest.php

@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+namespace RoaveTest\BackwardCompatibility\VersionConstraint;
+
+use PHPUnit\Framework\TestCase;
+use Roave\BackwardCompatibility\VersionConstraint\StableVersionConstraint;
+use Version\Version;
+
+final class StableVersionConstraintTest extends TestCase
+{
+    public function testStableVersions(): void
+    {
+        $constraint = new StableVersionConstraint();
+
+        self::assertTrue($constraint->assert(Version::fromString('1.0.0')));
+        self::assertTrue($constraint->assert(Version::fromString('0.1.0')));
+        self::assertTrue($constraint->assert(Version::fromString('0.0.1')));
+        self::assertFalse($constraint->assert(Version::fromString('1.0.0-alpha.1')));
+        self::assertFalse($constraint->assert(Version::fromString('1.0.0-beta.1')));
+        self::assertFalse($constraint->assert(Version::fromString('1.0.0-rc.1')));
+    }
+}