Bug 57010: Add implementation of function PROPER

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1633215 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/poi/ss/formula/eval/FunctionEval.java

@@ -207,7 +207,7 @@ public final class FunctionEval {
         retval[111] = TextFunction.CHAR;
         retval[112] = TextFunction.LOWER;
         retval[113] = TextFunction.UPPER;
-
+        retval[114] = TextFunction.PROPER;
         retval[115] = TextFunction.LEFT;
         retval[116] = TextFunction.RIGHT;
         retval[117] = TextFunction.EXACT;

src/java/org/apache/poi/ss/formula/functions/TextFunction.java

@@ -17,6 +17,8 @@
 
 package org.apache.poi.ss.formula.functions;
 
+import java.util.regex.Pattern;
+
 import org.apache.poi.ss.formula.eval.BoolEval;
 import org.apache.poi.ss.formula.eval.ErrorEval;
 import org.apache.poi.ss.formula.eval.EvaluationException;
@@ -112,6 +114,32 @@ public abstract class TextFunction implements Function {
 			return new StringEval(arg.toUpperCase());
 		}
 	};
+
+	/**
+	 * Implementation of the PROPER function:
+     * Normalizes all words (separated by non-word characters) by
+     * making the first letter upper and the rest lower case.
+	 */
+	public static final Function PROPER = new SingleArgTextFunc() {
+	    final Pattern nonAlphabeticPattern = Pattern.compile("\\P{IsL}");
+		protected ValueEval evaluate(String text) {
+			StringBuilder sb = new StringBuilder();
+			boolean shouldMakeUppercase = true;
+			String lowercaseText = text.toLowerCase();
+			String uppercaseText = text.toUpperCase();
+			for(int i = 0; i < text.length(); ++i) {
+				if (shouldMakeUppercase) {
+					sb.append(uppercaseText.charAt(i));
+				}
+				else {
+					sb.append(lowercaseText.charAt(i));
+				}
+				shouldMakeUppercase = nonAlphabeticPattern.matcher(text.subSequence(i, i + 1)).matches();
+			}
+			return new StringEval(sb.toString());
+		}
+	};
+
 	/**
 	 * An implementation of the TRIM function:
 	 * Removes leading and trailing spaces from value if evaluated operand

src/testcases/org/apache/poi/ss/formula/functions/TestProper.java

@@ -0,0 +1,86 @@
+/* ====================================================================
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+==================================================================== */
+
+package org.apache.poi.ss.formula.functions;
+
+import junit.framework.AssertionFailedError;
+import junit.framework.TestCase;
+
+import org.apache.poi.hssf.usermodel.HSSFFormulaEvaluator;
+import org.apache.poi.hssf.usermodel.HSSFWorkbook;
+import org.apache.poi.ss.usermodel.Cell;
+import org.apache.poi.ss.usermodel.CellValue;
+import org.apache.poi.ss.usermodel.FormulaEvaluator;
+import org.apache.poi.ss.usermodel.Sheet;
+import org.apache.poi.ss.usermodel.Workbook;
+import org.apache.poi.xssf.usermodel.XSSFCell;
+import org.apache.poi.xssf.usermodel.XSSFFormulaEvaluator;
+import org.apache.poi.xssf.usermodel.XSSFWorkbook;
+
+public final class TestProper extends TestCase {
+    private Cell cell11;
+    private FormulaEvaluator evaluator;
+
+    public void testValidHSSF() {
+        HSSFWorkbook wb = new HSSFWorkbook();
+        evaluator = new HSSFFormulaEvaluator(wb);
+
+        confirm(wb);
+    }
+
+    public void testValidXSSF() {
+        XSSFWorkbook wb = new XSSFWorkbook();
+        evaluator = new XSSFFormulaEvaluator(wb);
+
+        confirm(wb);
+    }
+
+    private void confirm(Workbook wb) {
+        Sheet sheet = wb.createSheet("new sheet");
+        cell11 = sheet.createRow(0).createCell(0);
+        cell11.setCellType(XSSFCell.CELL_TYPE_FORMULA);
+
+        confirm("PROPER(\"hi there\")", "Hi There");
+        confirm("PROPER(\"what's up\")", "What'S Up");
+        confirm("PROPER(\"I DON'T TH!NK SO!\")", "I Don'T Th!Nk So!");
+        confirm("PROPER(\"drÜbö'ä éloş|ëè \")", "Drübö'Ä Éloş|Ëè ");
+        confirm("PROPER(\"hi123 the123re\")", "Hi123 The123Re");
+        confirm("PROPER(\"-\")", "-");
+        confirm("PROPER(\"!§$\")", "!§$");
+        confirm("PROPER(\"/&%\")", "/&%");
+        
+        // also test longer string
+        StringBuilder builder = new StringBuilder("A");
+        StringBuilder expected = new StringBuilder("A");
+        for(int i = 1;i < 254;i++) {
+            builder.append((char)(65 + (i % 26)));
+            expected.append((char)(97 + (i % 26)));
+        }
+        confirm("PROPER(\"" + builder.toString() + "\")", expected.toString());
+    }
+
+    private void confirm(String formulaText, String expectedResult) {
+        cell11.setCellFormula(formulaText);
+        evaluator.clearAllCachedResultValues();
+        CellValue cv = evaluator.evaluate(cell11);
+        if (cv.getCellType() != Cell.CELL_TYPE_STRING) {
+            throw new AssertionFailedError("Wrong result type: " + cv.formatAsString());
+        }
+        String actualValue = cv.getStringValue();
+        assertEquals(expectedResult, actualValue);
+    }
+}