From ea716aafc1fb7ee2a283e39ef2adea147d993a38 Mon Sep 17 00:00:00 2001
From: gs2018git <gs2018git@gmail.com>
Date: Mon, 24 Dec 2018 17:28:01 -0500
Subject: [PATCH] #100 1> Handling empty sub string in countSubstr. 2> Unit
 test for the same.

---
 src/main/java/strman/Strman.java      |  7 +++++++
 src/test/java/strman/StrmanTests.java | 10 ++++++++++
 2 files changed, 17 insertions(+)

diff --git a/src/main/java/strman/Strman.java b/src/main/java/strman/Strman.java
index 9b1e3c2..2a69c53 100644
--- a/src/main/java/strman/Strman.java
+++ b/src/main/java/strman/Strman.java
@@ -1457,6 +1457,13 @@ private static void validate(String value, Predicate<String> predicate, final Su
 
     private static long countSubstr(String value, String subStr, boolean allowOverlapping, long count) {
         int position = value.indexOf(subStr);
+        
+		// There would be one empty sub-string in every string
+		// Ex: "str".indexOf("") is 0. Also, "str".substring(3) is ""
+		if (subStr.isEmpty()) {
+			return ++count;
+		}
+		
         if (position == -1) {
             return count;
         }
diff --git a/src/test/java/strman/StrmanTests.java b/src/test/java/strman/StrmanTests.java
index 8ab7ffe..d0236c0 100644
--- a/src/test/java/strman/StrmanTests.java
+++ b/src/test/java/strman/StrmanTests.java
@@ -231,6 +231,16 @@ public void countSubstrTestFixture_caseSensitiveFalseAndOverlappingFalse() throw
     public void countSubstrTestFixture_caseSensitiveTrueAndOverlappingTrue() throws Exception {
         assertThat(countSubstr("aaa", "aa", true, true), equalTo(2L));
     }
+    
+	@Test
+	public void countSubstr_shouldCountSubStrWithEmptySubStr() throws Exception {
+		assertThat(countSubstr("aaa", "", true, true), equalTo(1L));
+	}
+
+	@Test
+	public void countSubstr_shouldCountSubStrWithEmptyValueAndEmptySubStr() throws Exception {
+		assertThat(countSubstr("", "", true, true), equalTo(1L));
+	}
 
     @Test
     public void endsWith_caseSensitive_ShouldBeTrueWhenStringEndsWithSearchStr() throws Exception {