[gnome-calculator/gnome-3-32] Only allow entering one decimal point in each number (fixes #5)

[Robert Roth <robertroth src gnome org>]

commit 3940543a8749d89870014bd4b7828bf75d817db3
Author: Robert Roth <robert roth off gmail com>
Date:   Tue Apr 2 03:52:12 2019 +0300

    Only allow entering one decimal point in each number (fixes #5)

 lib/math-equation.vala | 35 +++++++++++++++++++++++++++++++----
 src/math-display.vala  |  1 +
 2 files changed, 32 insertions(+), 4 deletions(-)
---
diff --git a/lib/math-equation.vala b/lib/math-equation.vala
index da1da2e3..d460c355 100644
--- a/lib/math-equation.vala
+++ b/lib/math-equation.vala
@@ -796,8 +796,8 @@ public class MathEquation : Gtk.SourceBuffer
         var text = serializer.to_string (x);
 
         if (representation_base != 0)
-            serializer.set_representation_base (serializer.get_base ());
-        this.history_signal (get_current_state ().expression, x, serializer.get_base(), 
representation_base); /*emits signal to enter a new entry into history-view */
+            serializer.set_representation_base (number_base);
+        this.history_signal (get_current_state ().expression, x, number_base, representation_base); /*emits 
signal to enter a new entry into history-view */
         set_text (text, -1);
         state.ans = x;
 
@@ -893,7 +893,34 @@ public class MathEquation : Gtk.SourceBuffer
 
     public void insert_numeric_point ()
     {
-        insert (serializer.get_radix ().to_string ());
+        Gtk.TextIter iter_prev;
+        get_iter_at_mark (out iter_prev, get_insert ());
+        /** go back to the first digit of the currently entered number **/
+        while (iter_prev.backward_char () && (iter_prev.get_char () == serializer.get_thousands_separator ()
+                || iter_prev.get_char ().isdigit ()
+                || iter_prev.get_char () == serializer.get_radix ()))
+            ; // do nothing
+
+        if (!iter_prev.is_start ())
+            iter_prev.forward_char ();
+        var current_number = "";
+
+        /** find the currently entered number, ignoring thousand separators and including decimal point **/
+        while (iter_prev.get_char () == serializer.get_thousands_separator ()
+                || iter_prev.get_char ().isdigit ()
+                || iter_prev.get_char () == serializer.get_radix ()) {
+            if (iter_prev.get_char ().isdigit ()) {
+                current_number += iter_prev.get_char ().to_string ();
+            }
+            if (iter_prev.get_char () == serializer.get_radix ()) {
+                current_number += ".";
+            }
+            iter_prev.forward_char ();
+        }
+
+        /** if the current number doesn't contain decimal point yet, add one */
+        if (!current_number.contains ("."))
+            insert (serializer.get_radix ().to_string ());
     }
 
     public void insert_number (Number x)
@@ -924,7 +951,7 @@ public class MathEquation : Gtk.SourceBuffer
     private Number? parse (string text, out uint representation_base, out ErrorCode error_code = null, out 
string? error_token = null, out uint? error_start = null, out uint error_end = null)
     {
         var equation = new MEquation (this, text);
-        equation.base = serializer.get_base ();
+        equation.base = number_base;
         equation.wordlen = word_size;
         equation.angle_units = angle_units;
 
diff --git a/src/math-display.vala b/src/math-display.vala
index 238c18e0..a4268cf3 100644
--- a/src/math-display.vala
+++ b/src/math-display.vala
@@ -222,6 +222,7 @@ public class MathDisplay : Gtk.Viewport
         /* Numeric keypad will insert '.' or ',' depending on layout */
         if ((event.keyval == Gdk.Key.KP_Decimal) ||
             (event.keyval == Gdk.Key.KP_Separator) ||
+            (event.keyval == Gdk.Key.period) ||
             (event.keyval == Gdk.Key.decimalpoint) ||
             (event.keyval == Gdk.Key.comma))
         {