async_fstream cacheing

Author: flipcoder

.gitignore

@@ -1,4 +1,4 @@
 obj/
-bin/
+bin/test
 *.make
 Makefile

bin/test.txt

@@ -0,0 +1 @@
+test

include/kit/async/async_fstream.h

@@ -68,11 +68,24 @@ class async_fstream
                 [this]{return m_Filename;}
             );
         };
+        std::future<std::string> buffer() const {
+            return m_pCircuit->task<std::string>([this]{
+                _cache();
+                return m_Buffer;
+            });
+        }
 
         template<class T>
         std::future<T> with(std::function<T(std::fstream& f)> func) {
             return m_pCircuit->task<T>([this,func]{ return func(m_File); });
         }
+        template<class T>
+        std::future<T> with(std::function<T(const std::string&)> func) {
+            return m_pCircuit->task<T>([this,func]{
+                _cache();
+                return func(m_Buffer);
+            });
+        }
 
         std::future<void> invalidate() {
             return m_pCircuit->task<void>(
@@ -85,7 +98,7 @@ class async_fstream
                 [this]{_invalidate();_cache();}
             );
         }
-        std::future<void> cache() {
+        std::future<void> cache() const {
             return m_pCircuit->task<void>(
                 [this]{_cache();}
             );
@@ -103,9 +116,9 @@ class async_fstream
         void _invalidate() {
             m_Buffer.clear();
         }
-        void _cache() {
+        void _cache() const {
             if(m_Buffer.empty()){
-                m_File.seekg(0, std::ios::end);   
+                m_File.seekg(0, std::ios::end);
                 m_Buffer.reserve(m_File.tellg());
                 m_File.seekg(0, std::ios::beg);
                 m_Buffer.assign(
@@ -116,10 +129,10 @@ class async_fstream
         }
 
         Multiplexer::Circuit* const m_pCircuit;
-        std::fstream m_File;
+        mutable std::fstream m_File;
         std::string m_Filename;
 
-        std::string m_Buffer;
+        mutable std::string m_Buffer;
 };
 
 #endif

tests/async.test.cpp

@@ -305,7 +305,7 @@ TEST_CASE("Multiplexer","[multiplexer]") {
 }
 
 TEST_CASE("Coroutines","[coroutines]") {
-    SECTION("Coroutines inside multiplexer"){
+    SECTION("Interleaved"){
         // In most apps, we'd use the singleton multiplexer "MX"
         //   and use AWAIT() instead of AWAIT_MX(mx, ...)
         // But since we want to isolate the multiplexer across unit tests
@@ -414,6 +414,10 @@ TEST_CASE("async_fstream","[async_fstream]") {
                 return f.is_open();
             }).get() == true);
             REQUIRE(file.filename().get() == fn);
+            //std::string buf = file.with<string>([](const std::string& b){
+            //    return b;
+            //}).get();
+            REQUIRE(file.buffer().get() == "test\n"); // contents of file
             file.close().get();
             REQUIRE(file.filename().get() == "");