1 files changed, 115 insertions, 0 deletions
diff --git a/src/helper/units-test.cpp b/src/helper/units-test.cpp
new file mode 100644
index 000000000..1a983fece
--- /dev/null
+++ b/src/helper/units-test.cpp
@@ -0,0 +1,115 @@
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+#include <math.h>
+
+#include <glibmm/i18n.h>
+#include <helper/units.h>
+#include <utest/utest.h>
+
+
+/* N.B. Wrongly returns false if both near 0.  (Not a problem for current users.) */
+static bool
+approx_equal(double const x, double const y)
+{
+    return fabs(x / y - 1) < 1e-15;
+}
+
+static double
+sp_units_get_points(double const x, SPUnit const &unit)
+{
+    SPUnit const &pt_unit = sp_unit_get_by_id(SP_UNIT_PT);
+    double const px = sp_units_get_pixels(x, unit);
+    return sp_pixels_get_units(px, pt_unit);
+}
+
+static double
+sp_points_get_units(double const pts, SPUnit const &unit)
+{
+    SPUnit const &pt_unit = sp_unit_get_by_id(SP_UNIT_PT);
+    double const px = sp_units_get_pixels(pts, pt_unit);
+    return sp_pixels_get_units(px, unit);
+}
+
+static bool
+test_conversions()
+{
+    utest_start("sp_units_get_pixels, sp_pixels_get_units");
+
+    struct Case { double x; char const *abbr; double pts; } const tests[] = {
+        { 1.0, "pt", 1.0 },
+        { 5.0, "pt", 5.0 },
+        { 1.0, "in", 72.0 },
+        { 2.0, "in", 144.0 },
+        { 254., "mm", 720.0 },
+        { 254., "cm", 7200. },
+        { 254., "m", 720000. },
+        { 1.5, "mm", (15 * 72. / 254) }
+    };
+    for (unsigned i = 0; i < G_N_ELEMENTS(tests); ++i) {
+        char name[80];
+        Case const &c = tests[i];
+        SPUnit const &unit = *sp_unit_get_by_abbreviation(N_(c.abbr));
+
+        double const calc_pts = sp_units_get_points(c.x, unit);
+        snprintf(name, sizeof(name), "%.1f %s -> %.1f pt", c.x, c.abbr, c.pts);
+        UTEST_TEST(name) {
+            UTEST_ASSERT(approx_equal(calc_pts, c.pts));
+        }
+
+        double const calc_x = sp_points_get_units(c.pts, unit);
+        snprintf(name, sizeof(name), "%.1f pt -> %.1f %s", c.pts, c.x, c.abbr);
+        UTEST_TEST(name) {
+            UTEST_ASSERT(approx_equal(calc_x, c.x));
+        }
+
+        double tmp = c.x;
+        bool const converted_to_pts = sp_convert_distance(&tmp, &unit, SP_PS_UNIT);
+        snprintf(name, sizeof(name), "convert %.1f %s -> %.1f pt", c.x, c.abbr, c.pts);
+        UTEST_TEST(name) {
+            UTEST_ASSERT(converted_to_pts);
+            UTEST_ASSERT(approx_equal(tmp, c.pts));
+        }
+
+        tmp = c.pts;
+        bool const converted_from_pts = sp_convert_distance(&tmp, SP_PS_UNIT, &unit);
+        snprintf(name, sizeof(name), "convert %.1f pt -> %.1f %s", c.pts, c.x, c.abbr);
+        UTEST_TEST(name) {
+            UTEST_ASSERT(converted_from_pts);
+            UTEST_ASSERT(approx_equal(tmp, c.x));
+        }
+    }
+    return utest_end();
+}
+
+static bool
+test_unit_table()
+{
+    utest_start("unit table");
+    UTEST_TEST("sp_units_table_sane") {
+        UTEST_ASSERT(sp_units_table_sane());
+    }
+    return utest_end();
+}
+
+int
+main(int argc, char *argv[])
+{
+    int const ret = ( ( test_conversions()
+                        && test_unit_table() )
+                      ? EXIT_SUCCESS
+                      : EXIT_FAILURE );
+    return ret;
+}
+
+
+/*
+  Local Variables:
+  mode:c++
+  c-file-style:"stroustrup"
+  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+  indent-tabs-mode:nil
+  fill-column:99
+  End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :