diff --git a/src/common/instruction.h b/src/common/instruction.h
index 7903c6e..9d8fccc 100644
--- a/src/common/instruction.h
+++ b/src/common/instruction.h
@@ -38,7 +38,7 @@ class Instruction {
   Instruction(std::string stmt) {
 
     raw = trim( stmt );
-    std::vector<std::string> contents = splitInstruction( raw );
+    auto contents = splitInstruction( raw );
 
     if (contents[0] == "store") {
       oper = STORE;
@@ -139,9 +139,14 @@ class Instruction {
 
   // Trims the left and right spaces from a std::string
   static std::string trim(std::string sentence) {
-    size_t start = sentence.find_first_not_of(' ');
-    size_t end = sentence.find_last_not_of(' ');
-    return sentence.substr(start, (end -start)+1);
+    auto start = sentence.find_first_not_of(' ');
+    auto end = sentence.find_last_not_of(' ');
+
+    if (start != std::string::npos) {
+      return sentence.substr(start, (end -start)+1);
+    } else {
+      return "";
+    }
   }
 
   // Splits std::string into tokens substrings
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index b846bfa..1fb3ab6 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -28,11 +28,13 @@ link_libraries(${GTEST_LIBRARIES} pthread gtest_main gcov --coverage)
 
 # Link commonTests with what we want to test and
 # the GTest and pthread library
-add_executable(commonTests Common_Defs_gtest.cc)
-add_executable(critalSigTests CriticalSignatures_gtest.cc)
-add_executable(memoryActionsTests MemoryActions_gtest.cc)
+add_executable(commonDefsTests Common_Defs_gtest.cc)
+add_executable(commonCritalSigTests Common_CriticalSignatures_gtest.cc)
+add_executable(commonMemoryActionsTests Common_MemoryActions_gtest.cc)
+add_executable(commonInstructionTests Common_Instruction_gtest.cc)
 
 # Add tests for Ctest
-add_test(common_tests, commonTests)
-add_test(critical_signatures_tests, critalSigTests)
-add_test(memory_actions_tests, memoryActionsTests)
+add_test(common_defs_tests, commonDefsTests)
+add_test(common_critical_signatures_tests, commonCritalSigTests)
+add_test(common_memory_actions_tests, commonMemoryActionsTests)
+add_test(common_instruction_tests, commonInstructionTests)
diff --git a/test/CriticalSignatures_gtest.cc b/test/Common_CriticalSignatures_gtest.cc
similarity index 100%
rename from test/CriticalSignatures_gtest.cc
rename to test/Common_CriticalSignatures_gtest.cc
diff --git a/test/Common_Instruction_gtest.cc b/test/Common_Instruction_gtest.cc
new file mode 100644
index 0000000..8760329
--- /dev/null
+++ b/test/Common_Instruction_gtest.cc
@@ -0,0 +1,55 @@
+#include <gtest/gtest.h>
+
+#include "common/instruction.h"
+
+TEST(InstructionTests, CheckTrimHelperFunction) {
+  std::string raw_instruction(" store balance r6 ");
+  EXPECT_EQ(std::string("store balance r6"), Instruction::trim(raw_instruction));
+
+  EXPECT_TRUE(Instruction::trim("      ").empty());
+}
+
+TEST(InstructionTests, CheckSplitInstructionFunction) {
+  std::string raw_instruction(" store balance r6 ");
+  Instruction instr;
+  auto chunks = instr.splitInstruction(raw_instruction);
+
+  EXPECT_EQ(3UL, chunks.size());
+  EXPECT_EQ("store", chunks.at(0));
+  EXPECT_EQ("balance", chunks.at(1));
+  EXPECT_EQ("r6", chunks.at(2));
+}
+
+TEST(InstructionTests, CheckSplitInstructionFunctionEmptyString) {
+  std::string raw_instruction("   ");
+  Instruction instr;
+  auto chunks = instr.splitInstruction(raw_instruction);
+  EXPECT_EQ(0UL, chunks.size());
+}
+
+TEST(InstructionTests, CheckInstructionForStore) {
+  std::string raw_instruction(" store i32 %2, i32* %balance ");
+  Instruction instr(raw_instruction);
+  EXPECT_EQ(STORE, instr.oper);
+  EXPECT_EQ("%balance", instr.destination);
+  EXPECT_EQ("i32", instr.type);
+  EXPECT_EQ("%2", instr.operand1);
+  EXPECT_EQ("%2", instr.operand2);
+}
+
+TEST(InstructionTests, CheckInstructionForLoad) {
+  std::string raw_instruction(" %1 = load i32 * %balance");
+  Instruction instr(raw_instruction);
+  EXPECT_EQ(LOAD, instr.oper);
+  EXPECT_EQ("%1", instr.destination);
+  EXPECT_EQ("i32", instr.type);
+  EXPECT_EQ("%balance", instr.operand1);
+}
+
+TEST(InstructionTests, CheckInstructionForAlloca) {
+  std::string raw_instruction("%balance = alloca i32 , align 4 ");
+  Instruction instr(raw_instruction);
+  EXPECT_EQ(ALLOCA, instr.oper);
+  EXPECT_EQ("%balance", instr.destination);
+  EXPECT_EQ("i32", instr.type);
+}
diff --git a/test/MemoryActions_gtest.cc b/test/Common_MemoryActions_gtest.cc
similarity index 100%
rename from test/MemoryActions_gtest.cc
rename to test/Common_MemoryActions_gtest.cc