#2772: PhContainingUTF8 to print strings correctly

eo-runtime/src/main/java/EOorg/EOeolang/EOerror.java

@@ -32,6 +32,7 @@
 import org.eolang.Attr;
 import org.eolang.ExAbstract;
 import org.eolang.ExFailure;
+import org.eolang.PhContainingUTF8;
 import org.eolang.PhDefault;
 import org.eolang.Phi;
 import org.eolang.Versionized;
@@ -115,7 +116,7 @@ public static final class ExError extends ExAbstract {
          * @param enclosure Enclosure inside the error
          */
         public ExError(final Phi enclosure) {
-            super(enclosure.toString());
+            super(EOerror.ExError.safeMessage(enclosure));
             this.enc = enclosure;
         }
 
@@ -126,5 +127,29 @@ public ExError(final Phi enclosure) {
         public Phi enclosure() {
             return this.enc;
         }
+
+        /**
+         * Retrieve message from enclosure safely.
+         * @param enclosure Enclosure.
+         * @return String message.
+         * @checkstyle IllegalCatchCheck (20 lines)
+         */
+        private static String safeMessage(final Phi enclosure) {
+            String result;
+            if (enclosure == null) {
+                result = "null Phi";
+            } else {
+                try {
+                    result = new PhContainingUTF8(enclosure).toString();
+                } catch (final Throwable first) {
+                    try {
+                        result = enclosure.toString();
+                    } catch (final Throwable second) {
+                        result = enclosure.getClass().toString();
+                    }
+                }
+            }
+            return result;
+        }
     }
 }

eo-runtime/src/main/java/org/eolang/PhContainingUTF8.java

@@ -0,0 +1,89 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2016-2023 Objectionary.com
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package org.eolang;
+
+import java.nio.charset.StandardCharsets;
+
+/**
+ * Class to print {@link Phi} objects with UTF8 String data correctly.
+ * @since 0.35
+ * @checkstyle AbbreviationAsWordInNameCheck (5 lines)
+ */
+public final class PhContainingUTF8 implements Phi {
+
+    /**
+     * Origin.
+     */
+    private final Phi origin;
+
+    /**
+     * Ctor.
+     * @param origin Origin.
+     */
+    public PhContainingUTF8(final Phi origin) {
+        this.origin = origin;
+    }
+
+    @Override
+    public String toString() {
+        return String.format(
+            "{%s: Δ as String = \"%s\"}",
+            this.origin.toString(),
+            new String(
+                new Dataized(this.origin).take(),
+                StandardCharsets.UTF_8
+            )
+        );
+    }
+
+    @Override
+    public Phi copy() {
+        return this.origin.copy();
+    }
+
+    @Override
+    public Attr attr(final int pos) {
+        return this.origin.attr(pos);
+    }
+
+    @Override
+    public Attr attr(final String name) {
+        return this.origin.attr(name);
+    }
+
+    @Override
+    public String locator() {
+        return this.origin.locator();
+    }
+
+    @Override
+    public String forma() {
+        return this.origin.forma();
+    }
+
+    @Override
+    public String φTerm() {
+        return this.origin.φTerm();
+    }
+}

eo-runtime/src/test/java/EOorg/EOeolang/EOerrorTest.java

@@ -27,10 +27,17 @@
  */
 package EOorg.EOeolang;
 
+import org.eolang.AtComposite;
+import org.eolang.AtOnce;
 import org.eolang.Data;
 import org.eolang.Dataized;
+import org.eolang.ExAbstract;
+import org.eolang.PhCopy;
+import org.eolang.PhDefault;
 import org.eolang.PhWith;
 import org.eolang.Phi;
+import org.hamcrest.MatcherAssert;
+import org.hamcrest.Matchers;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 
@@ -55,4 +62,51 @@ void makesToxicObject() {
         );
     }
 
+    @Test
+    void getsReadableError() {
+        ExAbstract error = null;
+        try {
+            new Dataized(new MyError()).take();
+        } catch (final ExAbstract exc) {
+            error = exc;
+        }
+        assert error != null;
+        MatcherAssert.assertThat(
+            error.toString(),
+            Matchers.containsString("qwerty")
+        );
+    }
+
+    /**
+     * The object below.
+     * [] > my-error
+     *   error > @
+     *     "qwerty"
+     * @since 0.35
+     * @checkstyle JavadocStyleCheck
+     */
+    private static final class MyError extends PhDefault {
+
+        /**
+         * Ctor.
+         */
+        MyError() {
+            this.add(
+                "φ",
+                new AtOnce(
+                    new AtComposite(
+                        this,
+                        rho -> new PhWith(
+                            new PhCopy(
+                                Phi.Φ.attr("org").get().attr("eolang").get().attr("error").get()
+                            ),
+                            "α",
+                            new Data.ToPhi("qwerty")
+                        )
+                    )
+                )
+            );
+        }
+    }
+
 }