From e690ed5292e485f2599cd82e1291f5588dc47ad3 Mon Sep 17 00:00:00 2001
From: Alan Kligman <ack@mozilla.com>
Date: Fri, 26 Jul 2013 00:15:48 -0400
Subject: [PATCH] Unlink implementation and tests.

---
 dist/idbfs.js                  | 69 ++++++++++++++++++++++++++++++----
 examples/refactoring-test.html |  4 +-
 src/file-system.js             | 69 ++++++++++++++++++++++++++++++----
 tests/spec/idbfs.spec.js       | 48 ++++++++++++++++++++++-
 4 files changed, 173 insertions(+), 17 deletions(-)

diff --git a/dist/idbfs.js b/dist/idbfs.js
index 9e7184d..5ad51c3 100644
--- a/dist/idbfs.js
+++ b/dist/idbfs.js
@@ -6388,7 +6388,6 @@ define('src/file-system',['require','lodash','when','src/path','src/path','src/p
     var oldDirectoryData;
     var newDirectoryNode;
     var newDirectoryData;
-    var directoryEntry;
     var fileNode;
 
     find_node(objectStore, oldParentPath, read_old_directory_data);
@@ -6442,16 +6441,51 @@ define('src/file-system',['require','lodash','when','src/path','src/path','src/p
       if(error) {
         callback(error);
       } else {
-        read_object(objectStore, newDirectoryData[newname].id, read_file_node);
+        read_object(objectStore, newDirectoryData[newname].id, update_file_node);
       }
     }
 
-    function read_file_node(error, result) {
+    function update_file_node(error, result) {
       if(error) {
         callback(error);
       } else {
-        directoryEntry = result;
-        read_object(objectStore, directoryEntry.id, update_file_node);
+        fileNode = result;
+        fileNode.nlinks += 1
+        write_object(objectStore, fileNode, fileNode.id, callback);
+      }
+    };
+  };
+
+  function unlink_node(objectStore, path, callback) {
+    path = normalize(path);
+    name = basename(path);
+    parentPath = dirname(path);
+
+    var directoryNode;
+    var directoryData;
+    var fileNode;
+
+    find_node(objectStore, parentPath, read_directory_data);
+
+    function read_directory_data(error, result) {
+      if(error) {
+        callback(error);
+      } else {
+        directoryNode = result;
+        read_object(objectStore, directoryNode.data, check_if_file_exists);
+      }
+    };
+
+    function check_if_file_exists(error, result) {
+      if(error) {
+        callback(error);
+      } else {
+        directoryData = result;
+        if(!_(directoryData).has(name)) {
+          callback(new ENoEntry('a component of the path does not name an existing file'));
+        } else {
+          read_object(objectStore, directoryData[name].id, update_file_node);
+        }
       }
     };
 
@@ -6460,10 +6494,31 @@ define('src/file-system',['require','lodash','when','src/path','src/path','src/p
         callback(error);
       } else {
         fileNode = result;
-        fileNode.nlinks += 1
-        write_object(objectStore, fileNode, directoryEntry.id, callback);
+        fileNode.nlinks -= 1;
+        if(fileNode.nlinks < 1) {
+          delete_object(objectStore, fileNode.id, delete_file_data);
+        } else {
+          write_object(objectStore, fileNode, fileNode.id, update_directory_data);
+        }
       }
     };
+
+    function delete_file_data(error) {
+      if(error) {
+        callback(error);
+      } else {
+        delete_object(objectStore, fileNode.data, update_directory_data);
+      }
+    };
+
+    function update_directory_data(error) {
+      if(error) {
+        callback(error);
+      } else {
+        delete directoryData[name];
+        write_object(objectStore, directoryData, directoryNode.data, callback);
+      }
+    }
   };
 
   /*
diff --git a/examples/refactoring-test.html b/examples/refactoring-test.html
index 880a7c3..fa5bcc3 100644
--- a/examples/refactoring-test.html
+++ b/examples/refactoring-test.html
@@ -37,9 +37,9 @@ fs.open('/myfile', 'w+', function(error, fd) {
       fs.link('/myfile', '/myotherfile', function(error) {
         if(error) throw error;
         console.log('linked');
-        fs.stat('/myfile', function(error, stats) {
+        fs.unlink('/myfile', function(error) {
           if(error) throw error;
-          console.log(stats);
+          console.log('unlinked');
         });
       });
     });
diff --git a/src/file-system.js b/src/file-system.js
index 060821e..72eac26 100644
--- a/src/file-system.js
+++ b/src/file-system.js
@@ -588,7 +588,6 @@ define(function(require) {
     var oldDirectoryData;
     var newDirectoryNode;
     var newDirectoryData;
-    var directoryEntry;
     var fileNode;
 
     find_node(objectStore, oldParentPath, read_old_directory_data);
@@ -642,16 +641,51 @@ define(function(require) {
       if(error) {
         callback(error);
       } else {
-        read_object(objectStore, newDirectoryData[newname].id, read_file_node);
+        read_object(objectStore, newDirectoryData[newname].id, update_file_node);
       }
     }
 
-    function read_file_node(error, result) {
+    function update_file_node(error, result) {
       if(error) {
         callback(error);
       } else {
-        directoryEntry = result;
-        read_object(objectStore, directoryEntry.id, update_file_node);
+        fileNode = result;
+        fileNode.nlinks += 1
+        write_object(objectStore, fileNode, fileNode.id, callback);
+      }
+    };
+  };
+
+  function unlink_node(objectStore, path, callback) {
+    path = normalize(path);
+    name = basename(path);
+    parentPath = dirname(path);
+
+    var directoryNode;
+    var directoryData;
+    var fileNode;
+
+    find_node(objectStore, parentPath, read_directory_data);
+
+    function read_directory_data(error, result) {
+      if(error) {
+        callback(error);
+      } else {
+        directoryNode = result;
+        read_object(objectStore, directoryNode.data, check_if_file_exists);
+      }
+    };
+
+    function check_if_file_exists(error, result) {
+      if(error) {
+        callback(error);
+      } else {
+        directoryData = result;
+        if(!_(directoryData).has(name)) {
+          callback(new ENoEntry('a component of the path does not name an existing file'));
+        } else {
+          read_object(objectStore, directoryData[name].id, update_file_node);
+        }
       }
     };
 
@@ -660,10 +694,31 @@ define(function(require) {
         callback(error);
       } else {
         fileNode = result;
-        fileNode.nlinks += 1
-        write_object(objectStore, fileNode, directoryEntry.id, callback);
+        fileNode.nlinks -= 1;
+        if(fileNode.nlinks < 1) {
+          delete_object(objectStore, fileNode.id, delete_file_data);
+        } else {
+          write_object(objectStore, fileNode, fileNode.id, update_directory_data);
+        }
       }
     };
+
+    function delete_file_data(error) {
+      if(error) {
+        callback(error);
+      } else {
+        delete_object(objectStore, fileNode.data, update_directory_data);
+      }
+    };
+
+    function update_directory_data(error) {
+      if(error) {
+        callback(error);
+      } else {
+        delete directoryData[name];
+        write_object(objectStore, directoryData, directoryNode.data, callback);
+      }
+    }
   };
 
   /*
diff --git a/tests/spec/idbfs.spec.js b/tests/spec/idbfs.spec.js
index 438fd1b..638049c 100644
--- a/tests/spec/idbfs.spec.js
+++ b/tests/spec/idbfs.spec.js
@@ -810,4 +810,50 @@ describe('fs.unlink', function() {
   it('should be a function', function() {
     expect(typeof this.fs.unlink).toEqual('function');
   });
-});
\ No newline at end of file
+
+  it('should remove a link to an existing file', function() {
+    var complete1 = false;
+    var complete2 = false;
+    var _error, _stats;
+    var that = this;
+
+    that.fs.open('/myfile', 'w+', function(error, result) {
+      if(error) throw error;
+
+      var fd = result;
+      that.fs.close(fd, function(error) {
+        if(error) throw error;
+
+        that.fs.link('/myfile', '/myotherfile', function(error) {
+          if(error) throw error;
+
+          that.fs.unlink('/myfile', function(error) {
+            if(error) throw error;
+
+            that.fs.stat('/myfile', function(error, result) {
+              _error = error;
+              complete1 = true;
+            });
+
+            that.fs.stat('/myotherfile', function(error, result) {
+              if(error) throw error;
+
+              _stats = result;
+              complete2 = true;
+            });
+          });
+        });
+      });
+    });
+
+    waitsFor(function() {
+      return complete1 && complete2;
+    }, 'test to complete', DEFAULT_TIMEOUT);
+
+    runs(function() {
+      expect(_error).toBeDefined();
+      expect(_error).toBeDefined();
+      expect(_stats.nlinks).toEqual(1);
+    });
+  });
+});