#1602 Discover with versions

eo-maven-plugin/src/main/java/org/eolang/maven/AssembleMojo.java

@@ -194,7 +194,7 @@ public void exec() throws IOException {
         if (this.central == null) {
             this.central = new Central(this.project, this.session, this.manager);
         }
-        String before = this.tojos.status();
+        String before = this.scopedTojos().status();
         int cycle = 0;
         final Moja<?>[] mojas = {
             new Moja<>(ParseMojo.class),
@@ -211,7 +211,7 @@ public void exec() throws IOException {
             for (final Moja<?> moja : mojas) {
                 moja.copy(this).execute();
             }
-            final String after = this.tojos.status();
+            final String after = this.scopedTojos().status();
             ++cycle;
             if (Logger.isInfoEnabled(this)) {
                 Logger.info(

eo-maven-plugin/src/main/java/org/eolang/maven/DiscoverMojo.java

@@ -31,6 +31,7 @@
 import java.nio.file.Path;
 import java.util.Collection;
 import java.util.HashSet;
+import java.util.List;
 import java.util.TreeSet;
 import org.apache.maven.plugins.annotations.LifecyclePhase;
 import org.apache.maven.plugins.annotations.Mojo;
@@ -94,26 +95,33 @@ public void exec() throws IOException {
     private Collection<String> discover(final Path file)
         throws FileNotFoundException {
         final XML xml = new XMLDocument(file);
+        final List<String> base = new ListOf<>(
+            "//o[",
+            "not(starts-with(@base,'.'))",
+            "and @base != 'Q'",
+            "and @base != '^'",
+            "and @base != '$'",
+            "and @base != '&'",
+            "and not(@ref)"
+        );
+        final List<String> regular = new ListOf<>(base);
+        if (this.versioned) {
+            regular.add("and not(@ver)");
+        }
+        regular.add("]/@base");
         final Collection<String> names = new TreeSet<>(
-            new ListOf<>(
-                new Filtered<>(
-                    obj -> !obj.isEmpty(),
-                    xml.xpath(
-                        String.join(
-                            " ",
-                            "//o[",
-                            "not(starts-with(@base,'.'))",
-                            " and @base != 'Q'",
-                            " and @base != '^'",
-                            " and @base != '$'",
-                            " and @base != '&'",
-                            " and not(@ref)",
-                            "]/@base"
-                        )
-                    )
-                )
-            )
+            this.names(xml, regular)
         );
+        if (this.versioned) {
+            final List<String> versioned = new ListOf<>(base);
+            versioned.addAll(
+                new ListOf<>(
+                    "and @ver",
+                    "]/concat(@base,'|',@ver)"
+                )
+            );
+            names.addAll(this.names(xml, versioned));
+        }
         if (!xml.nodes("//o[@vararg]").isEmpty()) {
             names.add("org.eolang.tuple");
         }
@@ -131,4 +139,24 @@ private Collection<String> discover(final Path file)
         return names;
     }
 
+    /**
+     * Get list of object names from given XML by provided xpath.
+     * @param xml XML.
+     * @param xpath Xpath.
+     * @return List of object names.
+     * @checkstyle NonStaticMethodCheck (25 lines)
+     */
+    private List<String> names(final XML xml, final List<String> xpath) {
+        return new ListOf<>(
+            new Filtered<>(
+                obj -> !obj.isEmpty(),
+                xml.xpath(
+                    String.join(
+                        " ",
+                        xpath
+                    )
+                )
+            )
+        );
+    }
 }

eo-maven-plugin/src/main/java/org/eolang/maven/RegisterMojo.java

@@ -138,13 +138,6 @@ public void exec() throws IOException {
                 .withVersion(ParseMojo.ZERO)
                 .withVer(ParseMojo.ZERO);
             Logger.debug(this, "EO source %s registered", name);
-            if (this.external != null) {
-                this.externalTojos
-                    .add(name)
-                    .withSource(file.toAbsolutePath())
-                    .withVersion(ParseMojo.ZERO);
-                Logger.debug(this, "EO source %s registered (external)", name);
-            }
         }
         Logger.info(
             this, "Registered %d EO sources from %s to %s, included %s, excluded %s",

eo-maven-plugin/src/main/java/org/eolang/maven/SafeMojo.java

@@ -197,11 +197,20 @@ abstract class SafeMojo extends AbstractMojo {
     @Parameter(property = "eo.cache")
     protected Path cache = Paths.get(System.getProperty("user.home")).resolve(".eo");
 
+    /**
+     * Used for object versioning implementation.
+     * If set to TRUE, external tojos are used instead of foreign ones and all
+     * inherited Mojos behave a bit differently.
+     * @checkstyle VisibilityModifierCheck (10 lines)
+     */
+    @Parameter(property = "eo.versioned", defaultValue = "false")
+    protected boolean versioned;
+
     /**
      * Cached tojos.
      * @checkstyle VisibilityModifierCheck (5 lines)
      */
-    protected final ForeignTojos tojos = new ForeignTojos(
+    private final ForeignTojos tojos = new ForeignTojos(
         () -> Catalogs.INSTANCE.make(this.foreign.toPath(), this.foreignFormat),
         () -> this.scope
     );
@@ -318,7 +327,13 @@ public final void execute() throws MojoFailureException, MojoExecutionException
      * @checkstyle AnonInnerLengthCheck (100 lines)
      */
     protected final ForeignTojos scopedTojos() {
-        return this.tojos;
+        final ForeignTojos tjs;
+        if (this.external != null && this.versioned) {
+            tjs = this.externalTojos;
+        } else {
+            tjs = this.tojos;
+        }
+        return tjs;
     }
 
     /**

eo-maven-plugin/src/test/java/org/eolang/maven/DiscoverMojoTest.java

@@ -89,4 +89,38 @@ void discoversForDifferentScopes(@TempDir final Path tmp) throws IOException {
             Matchers.is(true)
         );
     }
+
+    @Test
+    void discoversWithVersions(@TempDir final Path tmp) throws IOException {
+        final FakeMaven maven = new FakeMaven(tmp)
+            .with("versioned", true)
+            .withProgram(
+                "+alias org.eolang.txt.sprintf\n",
+                "[] > main",
+                "  seq > @",
+                "    QQ.io.stdout|0.29.1",
+                "      sprintf|0.28.5",
+                "        \"Hello world\"",
+                "          TRUE"
+            )
+            .execute(new FakeMaven.Discover());
+        final String sprintf = "org.eolang.txt.sprintf|0.28.5";
+        final String stdout = "org.eolang.io.stdout|0.29.1";
+        MatcherAssert.assertThat(
+            String.format(
+                "External tojos have to contain %s object after discovering, but they don't",
+                sprintf
+            ),
+            maven.externalTojos().contains(sprintf),
+            Matchers.is(true)
+        );
+        MatcherAssert.assertThat(
+            String.format(
+                "External tojos should not contain %s object after discovering, but they did",
+                stdout
+            ),
+            maven.externalTojos().contains(stdout),
+            Matchers.is(false)
+        );
+    }
 }

eo-maven-plugin/src/test/java/org/eolang/maven/RegisterMojoTest.java

@@ -102,6 +102,7 @@ void registersInExternal(@TempDir final Path temp) throws IOException {
         final String source = "src/eo";
         final FakeMaven maven = new FakeMaven(temp)
             .with("sourcesDir", temp.resolve(source).toFile())
+            .with("versioned", true)
             .execute(new FakeMaven.Register());
         MatcherAssert.assertThat(
             String.format(
@@ -115,9 +116,13 @@ void registersInExternal(@TempDir final Path temp) throws IOException {
             Matchers.is(true)
         );
         MatcherAssert.assertThat(
-            "External and foreign tojos should have the same status after registering because of identical behaviour at the step but they didn't",
+            "External and foreign tojos should not have the same status after registering because external should replace foreign but they didn't",
             maven.foreignTojos().status(),
-            Matchers.equalTo(maven.externalTojos().status())
+            Matchers.not(
+                Matchers.equalTo(
+                    maven.externalTojos().status()
+                )
+            )
         );
     }
 }