[gnome-calculator/60-split-out-a-backend-library] gcalc: fix parsing integer constants

[Daniel Espinosa Ortiz <despinosa src gnome org>]

commit fececc406917e62b8f884ea7b55c003f71ea88a8
Author: Daniel Espinosa Ortiz <esodan gmail com>
Date:   Wed Jan 2 16:23:07 2019 -0600

    gcalc: fix parsing integer constants

 gcalc/gcalc-gconstant.vala       |  2 +-
 gcalc/gcalc-parser.vala          | 18 +++++++++++++++---
 tests/gcalc-main-interfaces.vala | 17 +++++++++++++----
 3 files changed, 29 insertions(+), 8 deletions(-)
---
diff --git a/gcalc/gcalc-gconstant.vala b/gcalc/gcalc-gconstant.vala
index f33a1d22..4658db80 100644
--- a/gcalc/gcalc-gconstant.vala
+++ b/gcalc/gcalc-gconstant.vala
@@ -19,7 +19,7 @@
  *      Daniel Espinosa <esodan gmail com>
  */
 public class GCalc.GConstant : GExpression, Constant {
-  private MPFR.Real real_value;
+  private MPFR.Real real_value = MPFR.Real (1000);
 
   construct {
     real_value.set_zero ();
diff --git a/gcalc/gcalc-parser.vala b/gcalc/gcalc-parser.vala
index 6c633744..316a9a78 100644
--- a/gcalc/gcalc-parser.vala
+++ b/gcalc/gcalc-parser.vala
@@ -27,7 +27,13 @@ public class GCalc.Parser : Object {
     SourceFileType type = SourceFileType.NONE;
     var sf = new SourceFile (context, type, "gcalc://", str);
     var scanner = new Vala.Scanner (sf);
-    var lines = str.split ("\n");
+    string[] lines;
+    if ("\n" in str) {
+      lines = str.split ("\n");
+    } else {
+      lines = new string [0];
+      lines[0] = str;
+    }
     Vala.TokenType token = Vala.TokenType.NONE;
     var expected = new Gee.ArrayList<Vala.TokenType> ();
     Expression current = null;
@@ -35,11 +41,16 @@ public class GCalc.Parser : Object {
     while (token != Vala.TokenType.EOF) {
       Vala.SourceLocation begin, end;
       token = scanner.read_token (out begin, out end);
+      if (token == Vala.TokenType.EOF) {
+        break;
+      }
       string n = token.to_string ();
       n = n.replace ("`", "");
       n = n.replace ("'", "");
-      string l = lines[begin.line];
-      n = l.substring (begin.column, end.column - begin.column);
+      string l = lines[begin.line - 1];
+      message ("Token: '%s' : Line: %d Column begin: %d Column end: %d Text: %s", n, begin.line, 
begin.column, end.column, l);
+      n = l.substring (begin.column - 1, end.column - begin.column + 1);
+      message ("Token text: %s", n);
       if (expected.size != 0 && !expected.contains (token)) {
         throw new ParserError.INVALID_TOKEN_ERROR ("Found an unexpected expression");
       }
@@ -96,6 +107,7 @@ public class GCalc.Parser : Object {
           var iexp = new GConstant.@double (double.parse (n));
           if (current == null) {
             current = new GPolynomial ();
+            eq.expressions.add (current);
           }
           if (current is Polynomial) {
             current.expressions.add (iexp);
diff --git a/tests/gcalc-main-interfaces.vala b/tests/gcalc-main-interfaces.vala
index e342d87d..48f36de7 100644
--- a/tests/gcalc-main-interfaces.vala
+++ b/tests/gcalc-main-interfaces.vala
@@ -23,12 +23,21 @@ class Tests {
   {
     GLib.Intl.setlocale (GLib.LocaleCategory.ALL, "");
     Test.init (ref args);
-    Test.add_func ("/gcalc/solver/initial",
+    Test.add_func ("/gcalc/parser/constant",
     ()=>{
       try {
-        var solv = new GCalc.GSolver () as Solver;
-        //var res = solv.solve ("4+4");
-        //message (res.to_string ());
+        var parser = new Parser ();
+        var eqman = new GMathEquationManager ();
+        parser.parse ("1", eqman);
+        assert (eqman.equations.get_n_items () == 1);
+        var eq = eqman.equations.get_item (0) as MathEquation;
+        assert (eq != null);
+        assert (eq.expressions.get_n_items () == 1);
+        var p = eq.expressions.get_item (0) as Polynomial;
+        assert (p != null);
+        assert (p.expressions.get_n_items () == 1);
+        var c = p.expressions.get_item (0) as Constant;
+        assert (c != null);
       } catch (GLib.Error error) {
         warning ("Error: %s", error.message);
       }