add a stripStart, can replace EraseLeadingChars

3 files changed, 74 insertions, 0 deletions

diff --git a/comphelper/inc/comphelper/string.hxx b/comphelper/inc/comphelper/string.hxx
index 00a1664016cf..e6b2d721099d 100644
--- a/comphelper/inc/comphelper/string.hxx
+++ b/comphelper/inc/comphelper/string.hxx
@@ -220,6 +220,27 @@ COMPHELPER_DLLPUBLIC rtl::OString remove(const rtl::OString &rIn,
 COMPHELPER_DLLPUBLIC rtl::OUString remove(const rtl::OUString &rIn,
     sal_Unicode c);
 
+/** Strips occurrences of a character from the start of the source string
+
+    @param rIn      The input OString
+    @param c        The character to be stripped from the beginning
+
+    @return         The resulting OString
+ */
+COMPHELPER_DLLPUBLIC rtl::OString stripStart(const rtl::OString &rIn,
+    sal_Char c);
+
+/** Strips occurrences of a character from the start of the source string
+
+    @param rIn      The input OUString
+    @param c        The character to be stripped from the beginning
+
+    @return         The resulting OUString
+ */
+COMPHELPER_DLLPUBLIC rtl::OUString stripStart(const rtl::OUString &rIn,
+    sal_Unicode c);
+
+
 /** Returns a token in the OString
 
   @param    token       the number of the token to return
diff --git a/comphelper/qa/string/test_string.cxx b/comphelper/qa/string/test_string.cxx
index 2ce6f2cff1bb..790519d07839 100644
--- a/comphelper/qa/string/test_string.cxx
+++ b/comphelper/qa/string/test_string.cxx
@@ -49,6 +49,7 @@ public:
     void testNatural();
     void testReplace();
     void testRemove();
+    void testStripStart();
     void testToken();
     void testDecimalStringToNumber();
     void testIsdigitAsciiString();
@@ -62,6 +63,7 @@ public:
     CPPUNIT_TEST(testNatural);
     CPPUNIT_TEST(testReplace);
     CPPUNIT_TEST(testRemove);
+    CPPUNIT_TEST(testStripStart);
     CPPUNIT_TEST(testToken);
     CPPUNIT_TEST(testDecimalStringToNumber);
     CPPUNIT_TEST(testIsdigitAsciiString);
@@ -430,6 +432,26 @@ void TestString::testRemove()
     CPPUNIT_ASSERT(aOut.isEmpty());
 }
 
+void TestString::testStripStart()
+{
+    ::rtl::OString aIn(RTL_CONSTASCII_STRINGPARAM("abc"));
+    ::rtl::OString aOut;
+
+    aOut = ::comphelper::string::stripStart(aIn, 'b');
+    CPPUNIT_ASSERT(aOut.equalsL(RTL_CONSTASCII_STRINGPARAM("abc")));
+
+    aOut = ::comphelper::string::stripStart(aIn, 'a');
+    CPPUNIT_ASSERT(aOut.equalsL(RTL_CONSTASCII_STRINGPARAM("bc")));
+
+    aIn = rtl::OString(RTL_CONSTASCII_STRINGPARAM("aaa"));
+    aOut = ::comphelper::string::stripStart(aIn, 'a');
+    CPPUNIT_ASSERT(aOut.isEmpty());
+
+    aIn = rtl::OString(RTL_CONSTASCII_STRINGPARAM("aba"));
+    aOut = ::comphelper::string::stripStart(aIn, 'a');
+    CPPUNIT_ASSERT(aOut.equalsL(RTL_CONSTASCII_STRINGPARAM("ba")));
+}
+
 void TestString::testToken()
 {
     ::rtl::OString aIn(RTL_CONSTASCII_STRINGPARAM("10.11.12"));
diff --git a/comphelper/source/misc/string.cxx b/comphelper/source/misc/string.cxx
index 8525e79bd4fc..09fb2684e7ce 100644
--- a/comphelper/source/misc/string.cxx
+++ b/comphelper/source/misc/string.cxx
@@ -169,6 +169,37 @@ rtl::OUString remove(const rtl::OUString &rIn, sal_Unicode c)
     return tmpl_remove<rtl::OUString, sal_Unicode, rtl::OUStringBuffer>(rIn, c);
 }
 
+namespace
+{
+    template <typename T, typename C> T tmpl_stripStart(const T &rIn,
+        const C cRemove)
+    {
+        if (rIn.isEmpty())
+            return rIn;
+
+        sal_Int32 i = 0;
+
+        while (i < rIn.getLength())
+        {
+            if (rIn[i] != cRemove)
+                break;
+            ++i;
+        }
+
+        return rIn.copy(i);
+    }
+}
+
+rtl::OString stripStart(const rtl::OString &rIn, sal_Char c)
+{
+    return tmpl_stripStart<rtl::OString, sal_Char>(rIn, c);
+}
+
+rtl::OUString stripStart(const rtl::OUString &rIn, sal_Unicode c)
+{
+    return tmpl_stripStart<rtl::OUString, sal_Unicode>(rIn, c);
+}
+
 sal_uInt32 decimalStringToNumber(
     ::rtl::OUString const & str )
 {