[maxima] properly parse plot and draw commands with line breaks.

src/backends/maxima/maximaexpression.cpp

@@ -157,11 +157,19 @@ QString MaximaExpression::internalCommand()
         const QString plotParameters = QLatin1String("[pdf_file, \"") + fileName + QLatin1String("\"], ") + pdfParam;
         */
 
+        //replace all newlines with spaces, as maxima isn't sensitive about
+        //whitespaces, and without newlines the whole command
+        //is executed at once, without outputting an input
+        //prompt after each line.
+        // Also, this helps to handle plot/draw commands  with line breaks that are not properly handled by the regex below.
+        cmd.replace(QLatin1Char('\n'), QLatin1Char(' '));
+
         if (!m_isDraw)
         {
             const QString plotParameters = QLatin1String("[gnuplot_png_term_command, \"set term png size 500,340\"], [png_file, \"") + m_tempFile->fileName() + QLatin1String("\"]");
             cmd.replace(QRegularExpression(QStringLiteral("((plot2d|plot3d|contour_plot)\\s*\\(.*)\\)([;\n$]|$)")),
                         QLatin1String("\\1, ") + plotParameters + QLatin1String(");"));
+
         }
         else
         {
@@ -181,12 +189,6 @@ QString MaximaExpression::internalCommand()
             cmd+=QLatin1Char(';');
     }
 
-    //replace all newlines with spaces, as maxima isn't sensitive about
-    //whitespaces, and without newlines the whole command
-    //is executed at once, without outputting an input
-    //prompt after each line
-    cmd.replace(QLatin1Char('\n'), QLatin1Char(' '));
-
     //lisp-quiet doesn't print a prompt after the command
     //is completed, which causes the parsing to hang.
     //replace the command with the non-quiet version

src/backends/maxima/testmaxima.cpp

@@ -70,6 +70,28 @@ void TestMaxima::testPlot()
     QVERIFY( e->errorMessage().isNull() );
 }
 
+void TestMaxima::testPlotMultiline()
+{
+    if(QStandardPaths::findExecutable(QLatin1String("gnuplot")).isNull())
+        QSKIP("gnuplot not found, maxima needs it for plotting", SkipSingle);
+
+    auto* e = evalExp(QLatin1String(
+                "plot2d (x^2-y^3+3*y=2,\n"
+                "[x,-2.5,2.5],\n"
+                "[y,-2.5,2.5])"
+    ));
+
+    QVERIFY(e != nullptr);
+    QVERIFY(e->result() != nullptr);
+
+    if(!e->result())
+        waitForSignal(e, SIGNAL(gotResult()));
+
+    QCOMPARE(e->result()->type(), (int)Cantor::ImageResult::Type);
+    QVERIFY(!e->result()->data().isNull());
+    QVERIFY(e->errorMessage().isNull());
+}
+
 void TestMaxima::testPlotWithAnotherTextResults()
 {
     if(QStandardPaths::findExecutable(QLatin1String("gnuplot")).isNull())
@@ -120,6 +142,41 @@ void TestMaxima::testDraw()
     QVERIFY( e->errorMessage().isNull() );
 }
 
+void TestMaxima::testDrawMultiline()
+{
+    if(QStandardPaths::findExecutable(QLatin1String("gnuplot")).isNull())
+        QSKIP("gnuplot not found, maxima needs it for plotting", SkipSingle);
+
+    auto* e = evalExp( QLatin1String(
+        "draw(\n"
+            "gr2d(\n"
+                "key=\"sin (x)\",grid=[2,2],\n"
+                "explicit(\n"
+                    "sin(x),\n"
+                    "x,0,2*%pi\n"
+                ")\n"
+            "),\n"
+            "gr2d(\n"
+                "key=\"cos (x)\",grid=[2,2],\n"
+                "explicit(\n"
+                    "cos(x),\n"
+                    "x,0,2*%pi\n"
+                ")\n"
+            "))"
+    ));
+
+
+    QVERIFY(e != nullptr);
+    QVERIFY(e->result() != nullptr);
+
+    if(!e->result())
+        waitForSignal(e, SIGNAL(gotResult()));
+
+    QCOMPARE(e->result()->type(), (int)Cantor::ImageResult::Type);
+    QVERIFY(!e->result()->data().isNull());
+    QVERIFY(e->errorMessage().isNull());
+}
+
 void TestMaxima::testDrawWithAnotherTextResults()
 {
     if(QStandardPaths::findExecutable(QLatin1String("gnuplot")).isNull())
@@ -148,7 +205,6 @@ void TestMaxima::testDrawWithAnotherTextResults()
     QCOMPARE(e->results().at(2)->data().toString(), QLatin1String("16"));
 }
 
-
 void TestMaxima::testInvalidSyntax()
 {
     auto* e=evalExp( QLatin1String("2+2*(") );

src/backends/maxima/testmaxima.h

@@ -25,10 +25,13 @@ private Q_SLOTS:
     void testMultilineCommand();
     //tests if the command queue works correctly
     void testCommandQueue();
+
     //tests doing a plot
     void testPlot();
+    void testPlotMultiline();
     void testPlotWithAnotherTextResults();
     void testDraw();
+    void testDrawMultiline();
     void testDrawWithAnotherTextResults();
 
     /* errors and warnings */