Created PropertyManager::ExpandOnce() that mimic the previous implementation of PropertyManager::Expand().

Modified PropertyManager::Expand() to expand the given string until all property references are expanded.
For issue #72.

Author: end2endzone

src/PropertyManager.cpp

@@ -129,6 +129,18 @@ namespace shellanything
   }
 
   std::string PropertyManager::Expand(const std::string & value) const
+  {
+    std::string previous = value;
+    std::string output = ExpandOnce(value);
+    while(output != previous)
+    {
+      previous = output;
+      output = ExpandOnce(output);
+    }
+    return output;
+  }
+
+  std::string PropertyManager::ExpandOnce(const std::string & value) const
   {
     //Process expansion in-place
     std::string output;

src/PropertyManager.h

@@ -90,10 +90,24 @@ namespace shellanything
     /// Expands the given string by replacing property variable reference by the actual variable's value.
     /// The syntax of a property variable reference is the following: `${variable-name}` where `variable-name` is the name of a variable.
     /// </summary>
+    /// <remarks>
+    /// The string is expanded until there are no change in the given string.
+    /// </remarks>
     /// <param name="value">The given value to expand.</param>
     /// <returns>Returns a copy of the given value with the property references expanded.</returns>
     std::string Expand(const std::string & value) const;
 
+    /// <summary>
+    /// Expands the given string by replacing property variable reference by the actual variable's value.
+    /// The syntax of a property variable reference is the following: `${variable-name}` where `variable-name` is the name of a variable.
+    /// </summary>
+    /// <remarks>
+    /// The string is expanded in a single pass. Some property reference may not be expanded after the first pass.
+    /// </remarks>
+    /// <param name="value">The given value to expand.</param>
+    /// <returns>Returns a copy of the given value with the property references expanded.</returns>
+    std::string ExpandOnce(const std::string & value) const;
+
   private:
 
     void RegisterEnvironmentVariables();

test/TestPropertyManager.cpp

@@ -115,7 +115,7 @@ namespace shellanything { namespace test
     ASSERT_EQ("The quick ${color fox jumps over the lazy dog.", expanded);
   }
   //--------------------------------------------------------------------------------------------------
-  TEST_F(TestPropertyManager, testExpandRecursivePermutations)
+  TEST_F(TestPropertyManager, testExpandPermutations)
   {
     PropertyManager & pmgr = PropertyManager::GetInstance();
 
@@ -213,6 +213,50 @@ namespace shellanything { namespace test
     ASSERT_EQ("E.T. phone home", expanded);
   }
   //--------------------------------------------------------------------------------------------------
+  TEST_F(TestPropertyManager, testExpandRecursive1)
+  {
+    PropertyManager & pmgr = PropertyManager::GetInstance();
+
+    pmgr.SetProperty("text1", "${text2}");
+    pmgr.SetProperty("text2", "${text3}");
+    pmgr.SetProperty("text3", "You're gonna need a bigger boat.");
+
+    //Property ${text1} should expand up to the expected movie quote.
+    std::string expanded = pmgr.Expand("${text1}");
+
+    //Assert the string was properly expanded.
+    ASSERT_EQ("You're gonna need a bigger boat.", expanded);
+  }
+  //--------------------------------------------------------------------------------------------------
+  TEST_F(TestPropertyManager, testExpandRecursive2)
+  {
+    PropertyManager & pmgr = PropertyManager::GetInstance();
+
+    pmgr.SetProperty("varname", "foo");
+    pmgr.SetProperty("foo", "${quote}");
+    pmgr.SetProperty("quote", "Say 'hello' to my little friend!");
+
+    //Property ${varname} should expand up to the expected movie quote.
+    std::string expanded = pmgr.Expand("${${varname}}");
+
+    //Assert the string was properly expanded.
+    ASSERT_EQ("Say 'hello' to my little friend!", expanded);
+  }
+  //--------------------------------------------------------------------------------------------------
+  TEST_F(TestPropertyManager, testExpandOnceDefault)
+  {
+    PropertyManager & pmgr = PropertyManager::GetInstance();
+
+    pmgr.SetProperty("varname", "quote");
+    pmgr.SetProperty("quote", "Say 'hello' to my little friend!");
+
+    //Property ${varname} should NOT expand up to the expected movie quote.
+    std::string expanded = pmgr.ExpandOnce("${${varname}}");
+
+    //Assert the string was properly expanded.
+    ASSERT_EQ("${quote}", expanded);
+  }
+  //--------------------------------------------------------------------------------------------------
   TEST_F(TestPropertyManager, testEnvironmentVariableProperty)
   {
     PropertyManager & pmgr = PropertyManager::GetInstance();