Implement areUnitsCompatible API method

We need this for the conversion dialog, where it's probably
better if we can avoid directly fiddling with UtUnits.

Change-Id: I090e59c49f3b77ffcc0571838023165c2da931a0

4 files changed, 30 insertions, 0 deletions

diff --git a/sc/inc/units.hxx b/sc/inc/units.hxx
index 381ec7dc08e1..1ba9121827dd 100644
--- a/sc/inc/units.hxx
+++ b/sc/inc/units.hxx
@@ -98,6 +98,9 @@ public:
                                   ScDocument* pDoc,
                                   const OUString& rsOutputUnit) = 0;
 
+    virtual bool areUnitsCompatible(const OUString& rsUnit1,
+                                    const OUString& rsUnit2) = 0;
+
     virtual ~Units() {}
 };
 
diff --git a/sc/qa/unit/units.cxx b/sc/qa/unit/units.cxx
index 1e202aa059e3..7e9e320e69ac 100644
--- a/sc/qa/unit/units.cxx
+++ b/sc/qa/unit/units.cxx
@@ -48,6 +48,7 @@ public:
 
     void testUnitFromHeaderExtraction();
 
+    void testUnitsCompatible();
     void testCellConversion();
     void testRangeConversion();
 
@@ -60,6 +61,7 @@ public:
     CPPUNIT_TEST(testUnitValueStringSplitting);
     CPPUNIT_TEST(testUnitFromHeaderExtraction);
 
+    CPPUNIT_TEST(testUnitsCompatible);
     CPPUNIT_TEST(testCellConversion);
     CPPUNIT_TEST(testRangeConversion);
 
@@ -471,6 +473,17 @@ void UnitsTest::testUnitFromHeaderExtraction() {
     CPPUNIT_ASSERT_EQUAL(aHeader.unitStringPosition, 8);
 }
 
+void UnitsTest::testUnitsCompatible() {
+    // This test is primarily to ensure that our glue works correctly, it's
+    // assumed that UdUnits is able to correctly parse the units / determine
+    // their compatibility.
+    CPPUNIT_ASSERT(mpUnitsImpl->areUnitsCompatible("cm", "m"));
+    CPPUNIT_ASSERT(mpUnitsImpl->areUnitsCompatible("ft", "m")); // Sorry!
+
+    CPPUNIT_ASSERT(!mpUnitsImpl->areUnitsCompatible("m", "kg"));
+    CPPUNIT_ASSERT(!mpUnitsImpl->areUnitsCompatible("s", "J"));
+}
+
 void UnitsTest::testCellConversion() {
     // We test both isCellConversionRecommended, and convertCellToHeaderUnit
     // since their arguments are essentially shared / dependent.
diff --git a/sc/source/core/units/unitsimpl.cxx b/sc/source/core/units/unitsimpl.cxx
index cca532d4614d..a7b103f31bf9 100644
--- a/sc/source/core/units/unitsimpl.cxx
+++ b/sc/source/core/units/unitsimpl.cxx
@@ -801,4 +801,15 @@ bool UnitsImpl::convertCellUnits(const ScRange& rRange,
     return true;
 }
 
+bool UnitsImpl::areUnitsCompatible(const OUString& rsUnit1, const OUString& rsUnit2) {
+    // TODO: in future we should have some sort of map< OUString, shared_ptr<set< OUString > >
+    // or similar to cache compatible units, as we may have a large number of such queries.
+
+    UtUnit aUnit1, aUnit2;
+
+    return UtUnit::createUnit(rsUnit1, aUnit1, mpUnitSystem)
+        && UtUnit::createUnit(rsUnit2, aUnit2, mpUnitSystem)
+        && aUnit1.areConvertibleTo(aUnit2);
+}
+
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sc/source/core/units/unitsimpl.hxx b/sc/source/core/units/unitsimpl.hxx
index 7320baad1d19..ff30232b2d19 100644
--- a/sc/source/core/units/unitsimpl.hxx
+++ b/sc/source/core/units/unitsimpl.hxx
@@ -107,6 +107,9 @@ public:
                                   ScDocument* pDoc,
                                   const OUString& rsOutputUnit) SAL_OVERRIDE;
 
+    virtual bool areUnitsCompatible(const OUString& rsUnit1,
+                                    const OUString& rsUnit2) SAL_OVERRIDE;
+
 private:
     UnitsResult getOutputUnitsForOpCode(std::stack< RAUSItem >& rStack, const formula::FormulaToken* pToken, ScDocument* pDoc);