[gcalctool] Add a --solve command-line argument

[Robert Ancell <rancell src gnome org>]

commit 64ea668b0d5532ed6abcdb6e20ba8bb15a3e5557
Author: Robert Ancell <robert ancell gmail com>
Date:   Thu May 7 11:49:48 2009 +1000

    Add a --solve command-line argument
    Mark command-line strings for translation
    Made program return 0 on success, 1 on failure
---
 ChangeLog            |    4 ++
 gcalctool/calctool.c |   93 +++++++++++++++++++++++++++++++++++---------------
 gcalctool/unittest.c |    9 +++--
 3 files changed, 75 insertions(+), 31 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 8869e6b..08faab5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -7,6 +7,10 @@
 gcalctool change history.
 =========================
 
+2009-05-07 Robert Ancell <robert ancell gmail com>
+
+    * Add a --solve command-line argument (Robert Ancell)
+
 2009-05-04 Robert Ancell <robert ancell gmail com>
 
     * Make GConf schemas translatable (Robert Ancell, Bug #571948)
diff --git a/gcalctool/calctool.c b/gcalctool/calctool.c
index f9f365f..16d622f 100644
--- a/gcalctool/calctool.c
+++ b/gcalctool/calctool.c
@@ -124,51 +124,71 @@ matherr(struct exception *exc)
 static void
 version()
 {
-    /* FIXME: Mark for translation post 2.26 */
+    /* NOTE: Is not translated so can be easily parsed */
     fprintf(stderr, "%1$s %2$s\n", v->progname, VERSION);
-    exit(1);
+}
+
+static void
+solve(const char *equation)
+{
+    int error;
+    MPNumber result;
+    char result_str[MAXLINE];
+    
+    error = ce_parse(equation, &result);
+    if(error != 0) {
+        fprintf(stderr, "Error %d\n", error);
+        exit(1);
+    }
+    else {
+        mp_cast_to_string(result_str, MAXLINE, &result, basevals[v->base], 9);
+        printf("%s\n", result_str);
+        exit(0);
+    }
 }
 
 static void
 usage(int show_gtk)
 {
-    /* FIXME: Mark for translation post 2.26 */
+    /* Translators: Description on how to use gcalctool displayed on command-line */
     fprintf(stderr,
-            "Usage:\n"
-            "  %s - Perform mathematical calculations\n", v->progname);
+            _("Usage:\n"
+              "  %s - Perform mathematical calculations"), v->progname);
 
     fprintf(stderr,
-            "\n");
+            "\n\n");
 
+    /* Translators: Description on gcalctool command-line help options displayed on command-line */
     fprintf(stderr,
-            "Help Options:\n"
-            "  -v, --version                   Show release version\n"
-            "  -h, -?, --help                  Show help options\n"
-            "  --help-all                      Show all help options\n"
-            "  --help-gtk                      Show GTK+ options\n");
+            _("Help Options:\n"
+              "  -v, --version                   Show release version\n"
+              "  -h, -?, --help                  Show help options\n"
+              "  --help-all                      Show all help options\n"
+              "  --help-gtk                      Show GTK+ options"));
     fprintf(stderr,
-            "\n");
+            "\n\n");
     
     if (show_gtk) {
-        fprintf(stderr,    
-                "GTK+ Options\n"
-                "  --class=CLASS                   Program class as used by the window manager\n"
-                "  --name=NAME                     Program name as used by the window manager\n"
-                "  --screen=SCREEN                 X screen to use\n"
-                "  --sync                          Make X calls synchronous\n"
-                "  --gtk-module=MODULES            Load additional GTK+ modules\n"
-                "  --g-fatal-warnings              Make all warnings fatal\n");
+        /* Translators: Description on gcalctool command-line GTK+ options displayed on command-line */
+        fprintf(stderr,
+                _("GTK+ Options:\n"
+                  "  --class=CLASS                   Program class as used by the window manager\n"
+                  "  --name=NAME                     Program name as used by the window manager\n"
+                  "  --screen=SCREEN                 X screen to use\n"
+                  "  --sync                          Make X calls synchronous\n"
+                  "  --gtk-module=MODULES            Load additional GTK+ modules\n"
+                  "  --g-fatal-warnings              Make all warnings fatal"));
         fprintf(stderr,
-                "\n");
+                "\n\n");
     }
 
+    /* Translators: Description on gcalctool application options displayed on command-line */    
     fprintf(stderr,
-            "Application Options:\n"
-            "  -u, --unittest                  Perform unittests\n");
+            _("Application Options:\n"
+              "  -u, --unittest                  Perform unittests\n"
+              "  -s, --solve <equation>          Solve the given equation"));
     fprintf(stderr,
-            "\n");
-
-    exit(1);
+            "\n\n");
 }
 
 void
@@ -184,22 +204,39 @@ get_options(int argc, char *argv[])
                  strcmp(arg, "--version") == 0 ||
                  strcmp(arg, "-?") == 0) {
             version();
+            exit(0);
         }
         else if (strcmp(arg, "-h") == 0 || 
                  strcmp(arg, "--help") == 0) {
             usage(FALSE);
+            exit(0);
         }
         else if (strcmp(arg, "--help-all") == 0) {
             usage(TRUE);
+            exit(0);
+        }
+        else if (strcmp(arg, "-s") == 0 ||
+            strcmp(arg, "--solve") == 0) {
+            i++;
+            if (i >= argc) {
+                /* Translators: Error printed to stderr when user uses --solve argument without an equation */
+                fprintf(stderr, _("Argument --solve requires an equation to solve"));
+                fprintf(stderr, "\n");
+                exit(1);
+            }
+            else
+                solve(argv[i]);
         }
         else if (strcmp(arg, "-u") == 0 ||
             strcmp(arg, "--unittest") == 0) {
             unittest();
         }
         else {
-            /* FIXME: Mark for translation post 2.26 */
-            fprintf(stderr, "Unknown argument '%s'\n", arg);
+            /* Translators: Error printed to stderr when user provides an unknown command-line argument */
+            fprintf(stderr, _("Unknown argument '%s'"), arg);
+            fprintf(stderr, "\n");
             usage(FALSE);
+            exit(1);
         }
     }
 }
diff --git a/gcalctool/unittest.c b/gcalctool/unittest.c
index 6d1d5aa..d204d0d 100644
--- a/gcalctool/unittest.c
+++ b/gcalctool/unittest.c
@@ -26,6 +26,8 @@
 #include "calctool.h"
 #include "ce_parser.h"
 
+static int fails = 0;
+
 static void
 test(char *expression, char *expected, int expected_error)
 {
@@ -44,8 +46,10 @@ test(char *expression, char *expected, int expected_error)
     }
     
     mp_cast_to_string(result_str, MAXLINE, &result, basevals[v->base], 9);
-    if(strcmp(result_str, expected) != 0)
+    if(strcmp(result_str, expected) != 0) {
+        fails++;
         printf("FAIL: '%s' -> '%s', expected '%s'\n", expression, result_str, expected);
+    }
     else
         printf("SUCCESS: '%s' -> '%s'\n", expression, result_str);
 }
@@ -201,6 +205,5 @@ void
 unittest()
 {
     test_parser();
-    
-    exit(1);    
+    exit(fails > 0 ? 1 : 0);
 }