Make the printing of complex Unicode in a QString prettier

This also has the advantage of not requiring the use of the locale
codec. Quite an advantage if you're debugging the locale codec. But it's
mostly so that we don't get question marks that hide the difference we
were trying to locate.

[ChangeLog][QtTest] QtTest now prints an escaped version of QStrings
that failed to compare with QCOMPARE. That is, instead of converting
non-printable characters to question marks, QtTest will print the
Unicode representation of the character in question.

Change-Id: I44c1ef3246b188c913dacd3ca4df02581356ea41
Reviewed-by: Lars Knoll <lars.knoll@digia.com>

src/testlib/qtest.h

@@ -66,14 +66,14 @@ QT_BEGIN_NAMESPACE
 namespace QTest
 {
 
-template<> inline char *toString(const QLatin1String &str)
-{
-    return qstrdup(qPrintable(QString(str)));
-}
-
 template<> inline char *toString(const QString &str)
 {
-    return qstrdup(qPrintable(str));
+    return QTest::toPrettyUnicode(reinterpret_cast<const ushort *>(str.constData()), str.length());
+}
+
+template<> inline char *toString(const QLatin1String &str)
+{
+    return toString(QString(str));
 }
 
 template<> inline char *toString(const QByteArray &ba)
@@ -195,15 +195,15 @@ inline bool qCompare(QList<T> const &t1, QList<T> const &t2, const char *actual,
     const int expectedSize = t2.count();
     if (actualSize != expectedSize) {
         qsnprintf(msg, sizeof(msg), "Compared lists have different sizes.\n"
-                  "   Actual   (%s) size: '%d'\n"
+                  "   Actual   (%s) size: %d\n"
-                  "   Expected (%s) size: '%d'", actual, actualSize, expected, expectedSize);
+                  "   Expected (%s) size: %d", actual, actualSize, expected, expectedSize);
         isOk = false;
     }
     for (int i = 0; isOk && i < actualSize; ++i) {
         if (!(t1.at(i) == t2.at(i))) {
             qsnprintf(msg, sizeof(msg), "Compared lists differ at index %d.\n"
-                      "   Actual   (%s): '%s'\n"
+                      "   Actual   (%s): %s\n"
-                      "   Expected (%s): '%s'", i, actual, toString(t1.at(i)),
+                      "   Expected (%s): %s", i, actual, toString(t1.at(i)),
                       expected, toString(t2.at(i)));
             isOk = false;
         }

src/testlib/qtestcase.cpp

@@ -1894,6 +1894,12 @@ void *fetchData(QTestData *data, const char *tagName, int typeId)
     return data->data(idx);
 }
 
+static char toHex(ushort value)
+{
+    static const char hexdigits[] = "0123456789ABCDEF";
+    return hexdigits[value & 0xF];
+}
+
 /*!
   \fn char* QTest::toHexRepresentation(const char *ba, int length)
 
@@ -1937,16 +1943,15 @@ char *toHexRepresentation(const char *ba, int length)
         result[size - 1] = '\0';
     }
 
-    const char toHex[] = "0123456789ABCDEF";
     int i = 0;
     int o = 0;
 
     while (true) {
         const char at = ba[i];
 
-        result[o] = toHex[(at >> 4) & 0x0F];
+        result[o] = toHex(at >> 4);
         ++o;
-        result[o] = toHex[at & 0x0F];
+        result[o] = toHex(at);
 
         ++i;
         ++o;
@@ -1961,6 +1966,61 @@ char *toHexRepresentation(const char *ba, int length)
     return result;
 }
 
+/*!
+    \internal
+    Returns the same QString but with only the ASCII characters still shown;
+    everything else is replaced with \c {\uXXXX}.
+*/
+char *toPrettyUnicode(const ushort *p, int length)
+{
+    // keep it simple for the vast majority of cases
+    QScopedArrayPointer<char> buffer(new char[length * 6 + 3]);
+    const ushort *end = p + length;
+    char *dst = buffer.data();
+
+    *dst++ = '"';
+    for ( ; p != end; ++p) {
+        if (*p < 0x7f && *p >= 0x20 && *p != '\\') {
+            *dst++ = *p;
+            continue;
+        }
+
+        // write as an escape sequence
+        *dst++ = '\\';
+        switch (*p) {
+        case 0x22:
+        case 0x5c:
+            *dst++ = uchar(*p);
+            break;
+        case 0x8:
+            *dst++ = 'b';
+            break;
+        case 0xc:
+            *dst++ = 'f';
+            break;
+        case 0xa:
+            *dst++ = 'n';
+            break;
+        case 0xd:
+            *dst++ = 'r';
+            break;
+        case 0x9:
+            *dst++ = 't';
+            break;
+        default:
+            *dst++ = 'u';
+            *dst++ = toHex(*p >> 12);
+            *dst++ = toHex(*p >> 8);
+            *dst++ = toHex(*p >> 4);
+            *dst++ = toHex(*p);
+        }
+    }
+
+    *dst++ = '"';
+    *dst++ = '\0';
+    return buffer.take();
+}
+
 static void qInvokeTestMethods(QObject *testObject)
 {
     const QMetaObject *metaObject = testObject->metaObject();

src/testlib/qtestcase.h

@@ -233,6 +233,7 @@ namespace QTest
 
 
     Q_TESTLIB_EXPORT char *toHexRepresentation(const char *ba, int length);
+    Q_TESTLIB_EXPORT char *toPrettyUnicode(const ushort *unicode, int length);
     Q_TESTLIB_EXPORT char *toString(const char *);
     Q_TESTLIB_EXPORT char *toString(const void *);
 

tests/auto/testlib/selftests/expected_cmptest.lightxml

@@ -54,48 +54,48 @@
 <Incident type="fail" file="tst_cmptest.cpp" line="313">
     <DataTag><![CDATA[last item different]]></DataTag>
     <Description><![CDATA[Compared lists differ at index 2.
-   Actual   (opA): 'string3'
+   Actual   (opA): "string3"
-   Expected (opB): 'DIFFERS']]></Description>
+   Expected (opB): "DIFFERS"]]></Description>
 </Incident>
 <Incident type="fail" file="tst_cmptest.cpp" line="313">
     <DataTag><![CDATA[second-last item different]]></DataTag>
     <Description><![CDATA[Compared lists differ at index 2.
-   Actual   (opA): 'string3'
+   Actual   (opA): "string3"
-   Expected (opB): 'DIFFERS']]></Description>
+   Expected (opB): "DIFFERS"]]></Description>
 </Incident>
 <Incident type="fail" file="tst_cmptest.cpp" line="313">
     <DataTag><![CDATA[prefix]]></DataTag>
     <Description><![CDATA[Compared lists have different sizes.
-   Actual   (opA) size: '2'
+   Actual   (opA) size: 2
-   Expected (opB) size: '1']]></Description>
+   Expected (opB) size: 1]]></Description>
 </Incident>
 <Incident type="fail" file="tst_cmptest.cpp" line="313">
     <DataTag><![CDATA[short list second]]></DataTag>
     <Description><![CDATA[Compared lists have different sizes.
-   Actual   (opA) size: '12'
+   Actual   (opA) size: 12
-   Expected (opB) size: '1']]></Description>
+   Expected (opB) size: 1]]></Description>
 </Incident>
 <Incident type="fail" file="tst_cmptest.cpp" line="313">
     <DataTag><![CDATA[short list first]]></DataTag>
     <Description><![CDATA[Compared lists have different sizes.
-   Actual   (opA) size: '1'
+   Actual   (opA) size: 1
-   Expected (opB) size: '12']]></Description>
+   Expected (opB) size: 12]]></Description>
 </Incident>
 <Duration msecs="0"/>
 </TestFunction>
 <TestFunction name="compareQListInt">
 <Incident type="fail" file="tst_cmptest.cpp" line="320">
     <Description><![CDATA[Compared lists differ at index 2.
-   Actual   (int1): '3'
+   Actual   (int1): 3
-   Expected (int2): '4']]></Description>
+   Expected (int2): 4]]></Description>
 </Incident>
 <Duration msecs="0"/>
 </TestFunction>
 <TestFunction name="compareQListDouble">
 <Incident type="fail" file="tst_cmptest.cpp" line="327">
     <Description><![CDATA[Compared lists differ at index 0.
-   Actual   (double1): '1.5'
+   Actual   (double1): 1.5
-   Expected (double2): '1']]></Description>
+   Expected (double2): 1]]></Description>
 </Incident>
 <Duration msecs="0"/>
 </TestFunction>

tests/auto/testlib/selftests/expected_cmptest.txt

@@ -23,32 +23,32 @@ FAIL!  : tst_Cmptest::compare_tostring(both non-null user type) Compared values
 PASS   : tst_Cmptest::compareQStringLists(empty lists)
 PASS   : tst_Cmptest::compareQStringLists(equal lists)
 FAIL!  : tst_Cmptest::compareQStringLists(last item different) Compared lists differ at index 2.
-   Actual   (opA): 'string3'
+   Actual   (opA): "string3"
-   Expected (opB): 'DIFFERS'
+   Expected (opB): "DIFFERS"
    Loc: [tst_cmptest.cpp(313)]
 FAIL!  : tst_Cmptest::compareQStringLists(second-last item different) Compared lists differ at index 2.
-   Actual   (opA): 'string3'
+   Actual   (opA): "string3"
-   Expected (opB): 'DIFFERS'
+   Expected (opB): "DIFFERS"
    Loc: [tst_cmptest.cpp(313)]
 FAIL!  : tst_Cmptest::compareQStringLists(prefix) Compared lists have different sizes.
-   Actual   (opA) size: '2'
+   Actual   (opA) size: 2
-   Expected (opB) size: '1'
+   Expected (opB) size: 1
    Loc: [tst_cmptest.cpp(313)]
 FAIL!  : tst_Cmptest::compareQStringLists(short list second) Compared lists have different sizes.
-   Actual   (opA) size: '12'
+   Actual   (opA) size: 12
-   Expected (opB) size: '1'
+   Expected (opB) size: 1
    Loc: [tst_cmptest.cpp(313)]
 FAIL!  : tst_Cmptest::compareQStringLists(short list first) Compared lists have different sizes.
-   Actual   (opA) size: '1'
+   Actual   (opA) size: 1
-   Expected (opB) size: '12'
+   Expected (opB) size: 12
    Loc: [tst_cmptest.cpp(313)]
 FAIL!  : tst_Cmptest::compareQListInt() Compared lists differ at index 2.
-   Actual   (int1): '3'
+   Actual   (int1): 3
-   Expected (int2): '4'
+   Expected (int2): 4
    Loc: [tst_cmptest.cpp(320)]
 FAIL!  : tst_Cmptest::compareQListDouble() Compared lists differ at index 0.
-   Actual   (double1): '1.5'
+   Actual   (double1): 1.5
-   Expected (double2): '1'
+   Expected (double2): 1
    Loc: [tst_cmptest.cpp(327)]
 PASS   : tst_Cmptest::compareQPixmaps(both null)
 FAIL!  : tst_Cmptest::compareQPixmaps(one null) Compared QPixmaps differ.

tests/auto/testlib/selftests/expected_cmptest.xml

@@ -56,48 +56,48 @@
 <Incident type="fail" file="tst_cmptest.cpp" line="313">
     <DataTag><![CDATA[last item different]]></DataTag>
     <Description><![CDATA[Compared lists differ at index 2.
-   Actual   (opA): 'string3'
+   Actual   (opA): "string3"
-   Expected (opB): 'DIFFERS']]></Description>
+   Expected (opB): "DIFFERS"]]></Description>
 </Incident>
 <Incident type="fail" file="tst_cmptest.cpp" line="313">
     <DataTag><![CDATA[second-last item different]]></DataTag>
     <Description><![CDATA[Compared lists differ at index 2.
-   Actual   (opA): 'string3'
+   Actual   (opA): "string3"
-   Expected (opB): 'DIFFERS']]></Description>
+   Expected (opB): "DIFFERS"]]></Description>
 </Incident>
 <Incident type="fail" file="tst_cmptest.cpp" line="313">
     <DataTag><![CDATA[prefix]]></DataTag>
     <Description><![CDATA[Compared lists have different sizes.
-   Actual   (opA) size: '2'
+   Actual   (opA) size: 2
-   Expected (opB) size: '1']]></Description>
+   Expected (opB) size: 1]]></Description>
 </Incident>
 <Incident type="fail" file="tst_cmptest.cpp" line="313">
     <DataTag><![CDATA[short list second]]></DataTag>
     <Description><![CDATA[Compared lists have different sizes.
-   Actual   (opA) size: '12'
+   Actual   (opA) size: 12
-   Expected (opB) size: '1']]></Description>
+   Expected (opB) size: 1]]></Description>
 </Incident>
 <Incident type="fail" file="tst_cmptest.cpp" line="313">
     <DataTag><![CDATA[short list first]]></DataTag>
     <Description><![CDATA[Compared lists have different sizes.
-   Actual   (opA) size: '1'
+   Actual   (opA) size: 1
-   Expected (opB) size: '12']]></Description>
+   Expected (opB) size: 12]]></Description>
 </Incident>
 <Duration msecs="0"/>
 </TestFunction>
 <TestFunction name="compareQListInt">
 <Incident type="fail" file="tst_cmptest.cpp" line="320">
     <Description><![CDATA[Compared lists differ at index 2.
-   Actual   (int1): '3'
+   Actual   (int1): 3
-   Expected (int2): '4']]></Description>
+   Expected (int2): 4]]></Description>
 </Incident>
 <Duration msecs="0"/>
 </TestFunction>
 <TestFunction name="compareQListDouble">
 <Incident type="fail" file="tst_cmptest.cpp" line="327">
     <Description><![CDATA[Compared lists differ at index 0.
-   Actual   (double1): '1.5'
+   Actual   (double1): 1.5
-   Expected (double2): '1']]></Description>
+   Expected (double2): 1]]></Description>
 </Incident>
 <Duration msecs="0"/>
 </TestFunction>

tests/auto/testlib/selftests/expected_cmptest.xunitxml

@@ -23,30 +23,30 @@
   </testcase>
   <testcase result="fail" name="compareQStringLists">
     <failure tag="last item different" message="Compared lists differ at index 2.
-   Actual   (opA): &apos;string3&apos;
+   Actual   (opA): &quot;string3&quot;
-   Expected (opB): &apos;DIFFERS&apos;" result="fail"/>
+   Expected (opB): &quot;DIFFERS&quot;" result="fail"/>
     <failure tag="second&#x002D;last item different" message="Compared lists differ at index 2.
-   Actual   (opA): &apos;string3&apos;
+   Actual   (opA): &quot;string3&quot;
-   Expected (opB): &apos;DIFFERS&apos;" result="fail"/>
+   Expected (opB): &quot;DIFFERS&quot;" result="fail"/>
     <failure tag="prefix" message="Compared lists have different sizes.
-   Actual   (opA) size: &apos;2&apos;
+   Actual   (opA) size: 2
-   Expected (opB) size: &apos;1&apos;" result="fail"/>
+   Expected (opB) size: 1" result="fail"/>
     <failure tag="short list second" message="Compared lists have different sizes.
-   Actual   (opA) size: &apos;12&apos;
+   Actual   (opA) size: 12
-   Expected (opB) size: &apos;1&apos;" result="fail"/>
+   Expected (opB) size: 1" result="fail"/>
     <failure tag="short list first" message="Compared lists have different sizes.
-   Actual   (opA) size: &apos;1&apos;
+   Actual   (opA) size: 1
-   Expected (opB) size: &apos;12&apos;" result="fail"/>
+   Expected (opB) size: 12" result="fail"/>
   </testcase>
   <testcase result="fail" name="compareQListInt">
     <failure message="Compared lists differ at index 2.
-   Actual   (int1): &apos;3&apos;
+   Actual   (int1): 3
-   Expected (int2): &apos;4&apos;" result="fail"/>
+   Expected (int2): 4" result="fail"/>
   </testcase>
   <testcase result="fail" name="compareQListDouble">
     <failure message="Compared lists differ at index 0.
-   Actual   (double1): &apos;1.5&apos;
+   Actual   (double1): 1.5
-   Expected (double2): &apos;1&apos;" result="fail"/>
+   Expected (double2): 1" result="fail"/>
   </testcase>
   <testcase result="fail" name="compareQPixmaps">
     <failure tag="one null" message="Compared QPixmaps differ.

tests/auto/testlib/selftests/expected_subtest.lightxml

@@ -125,8 +125,8 @@
 <Incident type="fail" file="tst_subtest.cpp" line="154">
     <DataTag><![CDATA[data1]]></DataTag>
     <Description><![CDATA[Compared values are not the same
-   Actual   (str)              : hello1
+   Actual   (str)              : "hello1"
-   Expected (QString("hello0")): hello0]]></Description>
+   Expected (QString("hello0")): "hello0"]]></Description>
 </Incident>
 <Message type="qdebug" file="" line="0">
     <DataTag><![CDATA[data1]]></DataTag>
@@ -143,8 +143,8 @@
 <Incident type="fail" file="tst_subtest.cpp" line="154">
     <DataTag><![CDATA[data2]]></DataTag>
     <Description><![CDATA[Compared values are not the same
-   Actual   (str)              : hello2
+   Actual   (str)              : "hello2"
-   Expected (QString("hello0")): hello0]]></Description>
+   Expected (QString("hello0")): "hello0"]]></Description>
 </Incident>
 <Message type="qdebug" file="" line="0">
     <DataTag><![CDATA[data2]]></DataTag>

tests/auto/testlib/selftests/expected_subtest.txt

@@ -33,15 +33,15 @@ PASS   : tst_Subtest::test3(data0)
 QDEBUG : tst_Subtest::test3(data1) init test3 data1
 QDEBUG : tst_Subtest::test3(data1) test2 test3 data1
 FAIL!  : tst_Subtest::test3(data1) Compared values are not the same
-   Actual   (str)              : hello1
+   Actual   (str)              : "hello1"
-   Expected (QString("hello0")): hello0
+   Expected (QString("hello0")): "hello0"
    Loc: [tst_subtest.cpp(154)]
 QDEBUG : tst_Subtest::test3(data1) cleanup test3 data1
 QDEBUG : tst_Subtest::test3(data2) init test3 data2
 QDEBUG : tst_Subtest::test3(data2) test2 test3 data2
 FAIL!  : tst_Subtest::test3(data2) Compared values are not the same
-   Actual   (str)              : hello2
+   Actual   (str)              : "hello2"
-   Expected (QString("hello0")): hello0
+   Expected (QString("hello0")): "hello0"
    Loc: [tst_subtest.cpp(154)]
 QDEBUG : tst_Subtest::test3(data2) cleanup test3 data2
 QDEBUG : tst_Subtest::cleanupTestCase() cleanupTestCase cleanupTestCase (null)

tests/auto/testlib/selftests/expected_subtest.xml

@@ -127,8 +127,8 @@
 <Incident type="fail" file="tst_subtest.cpp" line="154">
     <DataTag><![CDATA[data1]]></DataTag>
     <Description><![CDATA[Compared values are not the same
-   Actual   (str)              : hello1
+   Actual   (str)              : "hello1"
-   Expected (QString("hello0")): hello0]]></Description>
+   Expected (QString("hello0")): "hello0"]]></Description>
 </Incident>
 <Message type="qdebug" file="" line="0">
     <DataTag><![CDATA[data1]]></DataTag>
@@ -145,8 +145,8 @@
 <Incident type="fail" file="tst_subtest.cpp" line="154">
     <DataTag><![CDATA[data2]]></DataTag>
     <Description><![CDATA[Compared values are not the same
-   Actual   (str)              : hello2
+   Actual   (str)              : "hello2"
-   Expected (QString("hello0")): hello0]]></Description>
+   Expected (QString("hello0")): "hello0"]]></Description>
 </Incident>
 <Message type="qdebug" file="" line="0">
     <DataTag><![CDATA[data2]]></DataTag>

tests/auto/testlib/selftests/expected_subtest.xunitxml

@@ -38,14 +38,14 @@
     <!-- tag="data1" message="init test3 data1" type="qdebug" -->
     <!-- tag="data1" message="test2 test3 data1" type="qdebug" -->
     <failure tag="data1" message="Compared values are not the same
-   Actual   (str)              : hello1
+   Actual   (str)              : &quot;hello1&quot;
-   Expected (QString(&quot;hello0&quot;)): hello0" result="fail"/>
+   Expected (QString(&quot;hello0&quot;)): &quot;hello0&quot;" result="fail"/>
     <!-- tag="data1" message="cleanup test3 data1" type="qdebug" -->
     <!-- tag="data2" message="init test3 data2" type="qdebug" -->
     <!-- tag="data2" message="test2 test3 data2" type="qdebug" -->
     <failure tag="data2" message="Compared values are not the same
-   Actual   (str)              : hello2
+   Actual   (str)              : &quot;hello2&quot;
-   Expected (QString(&quot;hello0&quot;)): hello0" result="fail"/>
+   Expected (QString(&quot;hello0&quot;)): &quot;hello0&quot;" result="fail"/>
     <!-- tag="data2" message="cleanup test3 data2" type="qdebug" -->
   </testcase>
   <testcase result="pass" name="cleanupTestCase">