diff --git a/src/compiler/core.ts b/src/compiler/core.ts
index 4e03273537a..7c68306211a 100644
--- a/src/compiler/core.ts
+++ b/src/compiler/core.ts
@@ -1097,7 +1097,9 @@ namespace ts {
         return path.replace(/\\/g, "/");
     }
 
-    // Returns length of path root (i.e. length of "/", "x:/", "//server/share/, file:///user/files")
+    /**
+     * Returns length of path root (i.e. length of "/", "x:/", "//server/share/, file:///user/files")
+    */
     export function getRootLength(path: string): number {
         if (path.charCodeAt(0) === CharacterCodes.slash) {
             if (path.charCodeAt(1) !== CharacterCodes.slash) return 1;
@@ -1126,9 +1128,14 @@ namespace ts {
         return 0;
     }
 
+    /**
+     * Internally, we represent paths as strings with '/' as the directory separator.
+     * When we make system calls (eg: LanguageServiceHost.getDirectory()),
+     * we expect the host to correctly handle paths in our specified format.
+     */
     export const directorySeparator = "/";
     const directorySeparatorCharCode = CharacterCodes.slash;
-    function getNormalizedParts(normalizedSlashedPath: string, rootLength: number) {
+    function getNormalizedParts(normalizedSlashedPath: string, rootLength: number): string[] {
         const parts = normalizedSlashedPath.substr(rootLength).split(directorySeparator);
         const normalized: string[] = [];
         for (const part of parts) {
@@ -1168,6 +1175,11 @@ namespace ts {
         return path.charCodeAt(path.length - 1) === directorySeparatorCharCode;
     }
 
+    /**
+     * Returns the path except for its basename. Eg:
+     * 
+     * /path/to/file.ext -> /path/to
+     */
     export function getDirectoryPath(path: Path): Path;
     export function getDirectoryPath(path: string): string;
     export function getDirectoryPath(path: string): any {
diff --git a/src/server/lsHost.ts b/src/server/lsHost.ts
index 5b33770ce28..dedbb14c929 100644
--- a/src/server/lsHost.ts
+++ b/src/server/lsHost.ts
@@ -171,12 +171,16 @@ namespace ts.server {
             return this.host.fileExists(path);
         }
 
+        readFile(fileName: string): string {
+            return this.host.readFile(fileName);
+        }
+
         directoryExists(path: string): boolean {
             return this.host.directoryExists(path);
         }
 
-        readFile(fileName: string): string {
-            return this.host.readFile(fileName);
+        readDirectory(path: string, extensions?: string[], exclude?: string[], include?: string[]): string[] {
+            return this.host.readDirectory(path, extensions, exclude, include);
         }
 
         getDirectories(path: string): string[] {
diff --git a/src/services/completions.ts b/src/services/completions.ts
index 3fff0df5f9e..c8d7c019e54 100644
--- a/src/services/completions.ts
+++ b/src/services/completions.ts
@@ -325,15 +325,28 @@ namespace ts.Completions {
             return result;
         }
 
+        /**
+         * Given a path ending at a directory, gets the completions for the path, and filters for those entries containing the basename.
+         */
         function getCompletionEntriesForDirectoryFragment(fragment: string, scriptPath: string, extensions: string[], includeExtensions: boolean, span: TextSpan, exclude?: string, result: CompletionEntry[] = []): CompletionEntry[] {
+            if (fragment === undefined) {
+                fragment = "";
+            }
+
+            fragment = normalizeSlashes(fragment);
+
+            /**
+             * Remove the basename from the path. Note that we don't use the basename to filter completions;
+             * the client is responsible for refining completions.
+             */
             fragment = getDirectoryPath(fragment);
-            if (!fragment) {
-                fragment = "./";
-            }
-            else {
-                fragment = ensureTrailingDirectorySeparator(fragment);
+
+            if (fragment === "") {
+                fragment = "." + directorySeparator;
             }
 
+            fragment = ensureTrailingDirectorySeparator(fragment);
+
             const absolutePath = normalizeAndPreserveTrailingSlash(isRootedDiskPath(fragment) ? fragment : combinePaths(scriptPath, fragment));
             const baseDirectory = getDirectoryPath(absolutePath);
             const ignoreCase = !(host.useCaseSensitiveFileNames && host.useCaseSensitiveFileNames());
@@ -343,6 +356,12 @@ namespace ts.Completions {
                 const files = tryReadDirectory(host, baseDirectory, extensions, /*exclude*/undefined, /*include*/["./*"]);
 
                 if (files) {
+                    /**
+                     * Multiple file entries might map to the same truncated name once we remove extensions
+                     * (happens iff includeExtensions === false)so we use a set-like data structure. Eg:
+                     * 
+                     * both foo.ts and foo.tsx become foo
+                     */
                     const foundFiles = createMap<boolean>();
                     for (let filePath of files) {
                         filePath = normalizePath(filePath);
@@ -539,36 +558,44 @@ namespace ts.Completions {
                 return undefined;
             }
 
+            const completionInfo: CompletionInfo = {
+                /**
+                 * We don't want the editor to offer any other completions, such as snippets, inside a comment.
+                 */
+                isGlobalCompletion: false,
+                isMemberCompletion: false,
+                /**
+                 * The user may type in a path that doesn't yet exist, creating a "new identifier"
+                 * with respect to the collection of identifiers the server is aware of.
+                 */
+                isNewIdentifierLocation: true,
+
+                entries: []
+            };
+
             const text = sourceFile.text.substr(range.pos, position - range.pos);
 
             const match = tripleSlashDirectiveFragmentRegex.exec(text);
+
             if (match) {
                 const prefix = match[1];
                 const kind = match[2];
                 const toComplete = match[3];
 
                 const scriptPath = getDirectoryPath(sourceFile.path);
-                let entries: CompletionEntry[];
                 if (kind === "path") {
                     // Give completions for a relative path
                     const span: TextSpan = getDirectoryFragmentTextSpan(toComplete, range.pos + prefix.length);
-                    entries = getCompletionEntriesForDirectoryFragment(toComplete, scriptPath, getSupportedExtensions(compilerOptions), /*includeExtensions*/true, span, sourceFile.path);
+                    completionInfo.entries = getCompletionEntriesForDirectoryFragment(toComplete, scriptPath, getSupportedExtensions(compilerOptions), /*includeExtensions*/true, span, sourceFile.path);
                 }
                 else {
                     // Give completions based on the typings available
                     const span: TextSpan = { start: range.pos + prefix.length, length: match[0].length - prefix.length };
-                    entries = getCompletionEntriesFromTypings(host, compilerOptions, scriptPath, span);
+                    completionInfo.entries = getCompletionEntriesFromTypings(host, compilerOptions, scriptPath, span);
                 }
-
-                return {
-                    isGlobalCompletion: false,
-                    isMemberCompletion: false,
-                    isNewIdentifierLocation: true,
-                    entries
-                };
             }
 
-            return undefined;
+            return completionInfo;
         }
 
         function getCompletionEntriesFromTypings(host: LanguageServiceHost, options: CompilerOptions, scriptPath: string, span: TextSpan, result: CompletionEntry[] = []): CompletionEntry[] {
@@ -1674,9 +1701,15 @@ namespace ts.Completions {
      * Matches a triple slash reference directive with an incomplete string literal for its path. Used
      * to determine if the caret is currently within the string literal and capture the literal fragment
      * for completions.
-     * For example, this matches /// <reference path="fragment
+     * For example, this matches
+     * 
+     * /// <reference path="fragment
+     * 
+     * but not
+     *  
+     * /// <reference path="fragment"
      */
-    const tripleSlashDirectiveFragmentRegex = /^(\/\/\/\s*<reference\s+(path|types)\s*=\s*(?:'|"))([^\3]*)$/;
+    const tripleSlashDirectiveFragmentRegex = /^(\/\/\/\s*<reference\s+(path|types)\s*=\s*(?:'|"))([^\3"]*)$/;
 
     interface VisibleModuleInfo {
         moduleName: string;
diff --git a/src/services/types.ts b/src/services/types.ts
index f84986bb534..ac81a87daf5 100644
--- a/src/services/types.ts
+++ b/src/services/types.ts
@@ -505,7 +505,11 @@ namespace ts {
     export interface CompletionInfo {
         isGlobalCompletion: boolean;
         isMemberCompletion: boolean;
-        isNewIdentifierLocation: boolean;  // true when the current location also allows for a new identifier
+
+        /**
+         * true when the current location also allows for a new identifier
+         */
+        isNewIdentifierLocation: boolean;
         entries: CompletionEntry[];
     }
 
diff --git a/tests/cases/fourslash/completionForStringLiteralRelativeImport1.ts b/tests/cases/fourslash/completionForStringLiteralRelativeImport1.ts
deleted file mode 100644
index 3ba82fb0acf..00000000000
--- a/tests/cases/fourslash/completionForStringLiteralRelativeImport1.ts
+++ /dev/null
@@ -1,70 +0,0 @@
-/// <reference path='fourslash.ts' />
-
-// Should give completions for ts files when allowJs is false
-
-// @Filename: test0.ts
-//// import * as foo1 from "./*import_as0*/
-//// import * as foo2 from ".//*import_as1*/
-//// import * as foo4 from "./folder//*import_as2*/
-
-//// import foo6 = require("./*import_equals0*/
-//// import foo7 = require(".//*import_equals1*/
-//// import foo9 = require("./folder//*import_equals2*/
-
-//// var foo11 = require("./*require0*/
-//// var foo12 = require(".//*require1*/
-//// var foo14 = require("./folder//*require2*/
-
-// @Filename: parentTest/sub/test5.ts
-//// import * as foo16 from "../g/*import_as3*/
-//// import foo17 = require("../g/*import_equals3*/
-//// var foo18 = require("../g/*require3*/
-
-
-// @Filename: f1.ts
-//// /*f1*/
-// @Filename: f1.js
-//// /*f1j*/
-// @Filename: f1.d.ts
-//// /*f1d*/
-// @Filename: f2.tsx
-//// /f2*/
-// @Filename: f3.js
-//// /*f3*/
-// @Filename: f4.jsx
-//// /*f4*/
-// @Filename: e1.ts
-//// /*e1*/
-// @Filename: folder/f3.ts
-//// /*subf1*/
-// @Filename: folder/h1.ts
-//// /*subh1*/
-// @Filename: parentTest/f4.ts
-//// /*parentf1*/
-// @Filename: parentTest/g1.ts
-//// /*parentg1*/
-const kinds = ["import_as", "import_equals", "require"];
-
-for (const kind of kinds) {
-    goTo.marker(kind + "0");
-    verify.completionListIsEmpty();
-
-    goTo.marker(kind + "1");
-    verify.completionListContains("f1");
-    verify.completionListContains("f2");
-    verify.completionListContains("e1");
-    verify.completionListContains("folder");
-    verify.completionListContains("parentTest");
-    verify.not.completionListItemsCountIsGreaterThan(5);
-
-    goTo.marker(kind + "2");
-    verify.completionListContains("f3");
-    verify.completionListContains("h1");
-    verify.not.completionListItemsCountIsGreaterThan(2);
-
-    goTo.marker(kind + "3");
-    verify.completionListContains("f4");
-    verify.completionListContains("g1");
-    verify.completionListContains("sub");
-    verify.not.completionListItemsCountIsGreaterThan(3);
-}
\ No newline at end of file
diff --git a/tests/cases/fourslash/completionForStringLiteralRelativeImportAllowJSFalse.ts b/tests/cases/fourslash/completionForStringLiteralRelativeImportAllowJSFalse.ts
new file mode 100644
index 00000000000..f343ce8699b
--- /dev/null
+++ b/tests/cases/fourslash/completionForStringLiteralRelativeImportAllowJSFalse.ts
@@ -0,0 +1,72 @@
+/// <reference path='fourslash.ts' />
+
+// Should give completions for ts files only when allowJs is false.
+
+// @Filename: test0.ts
+//// import * as foo1 from "./*import_as0*/
+//// import * as foo2 from ".//*import_as1*/
+//// import * as foo4 from "./d1//*import_as2*/
+
+//// import foo6 = require("./*import_equals0*/
+//// import foo7 = require(".//*import_equals1*/
+//// import foo9 = require("./d1//*import_equals2*/
+
+//// var foo11 = require("./*require0*/
+//// var foo12 = require(".//*require1*/
+//// var foo14 = require("./d1//*require2*/
+
+// @Filename: d2/d3/test1.ts
+//// import * as foo16 from "..//*import_as3*/
+//// import foo17 = require("..//*import_equals3*/
+//// var foo18 = require("..//*require3*/
+
+
+// @Filename: f1.ts
+//// /*f1*/
+// @Filename: f2.js
+//// /*f2*/
+// @Filename: f3.d.ts
+//// /*f3*/
+// @Filename: f4.tsx
+//// /f4*/
+// @Filename: f5.js
+//// /*f5*/
+// @Filename: f6.jsx
+//// /*f6*/
+// @Filename: f7.ts
+//// /*f7*/
+// @Filename: d1/f8.ts
+//// /*d1f1*/
+// @Filename: d1/f9.ts
+//// /*d1f9*/
+// @Filename: d2/f10.ts
+//// /*d2f1*/
+// @Filename: d2/f11.ts
+//// /*d2f11*/
+
+const kinds = ["import_as", "import_equals", "require"];
+
+for (const kind of kinds) {
+    goTo.marker(kind + "0");
+    verify.completionListIsEmpty();
+
+    goTo.marker(kind + "1");
+    verify.completionListContains("f1");
+    verify.completionListContains("f3");
+    verify.completionListContains("f4");
+    verify.completionListContains("f7");
+    verify.completionListContains("d1");
+    verify.completionListContains("d2");
+    verify.not.completionListItemsCountIsGreaterThan(6);
+
+    goTo.marker(kind + "2");
+    verify.completionListContains("f8");
+    verify.completionListContains("f9");
+    verify.not.completionListItemsCountIsGreaterThan(2);
+
+    goTo.marker(kind + "3");
+    verify.completionListContains("f10");
+    verify.completionListContains("f11");
+    verify.completionListContains("d3");
+    verify.not.completionListItemsCountIsGreaterThan(3);
+}
\ No newline at end of file
diff --git a/tests/cases/fourslash/completionForStringLiteralRelativeImport2.ts b/tests/cases/fourslash/completionForStringLiteralRelativeImportAllowJSTrue.ts
similarity index 51%
rename from tests/cases/fourslash/completionForStringLiteralRelativeImport2.ts
rename to tests/cases/fourslash/completionForStringLiteralRelativeImportAllowJSTrue.ts
index 18a80ab3481..6eab9aaeca2 100644
--- a/tests/cases/fourslash/completionForStringLiteralRelativeImport2.ts
+++ b/tests/cases/fourslash/completionForStringLiteralRelativeImportAllowJSTrue.ts
@@ -1,6 +1,6 @@
 /// <reference path='fourslash.ts' />
 
-// Should give completions for ts and js files when allowJs is true
+// Should give completions for ts and js files when allowJs is true.
 
 // @allowJs: true
 
@@ -16,38 +16,33 @@
 
 // @Filename: f1.ts
 //// /f1*/
-// @Filename: f1.js
-//// /*f1j*/
-// @Filename: f1.d.ts
-//// /*f1d*/
-// @Filename: f2.tsx
+// @Filename: f2.js
 //// /*f2*/
-// @Filename: f3.js
+// @Filename: f3.d.ts
 //// /*f3*/
-// @Filename: f4.jsx
+// @Filename: f4.tsx
 //// /*f4*/
-// @Filename: e1.ts
-//// /*e1*/
-// @Filename: e2.js
-//// /*e2*/
+// @Filename: f5.js
+//// /*f5*/
+// @Filename: f6.jsx
+//// /*f6*/
+// @Filename: g1.ts
+//// /*g1*/
+// @Filename: g2.js
+//// /*g2*/
 const kinds = ["import_as", "import_equals", "require"];
 
 for (const kind of kinds) {
-    goTo.marker(kind + "0");
+    for(let i = 0; i < 2; ++i) {
+    goTo.marker(kind + i);
     verify.completionListContains("f1");
     verify.completionListContains("f2");
     verify.completionListContains("f3");
     verify.completionListContains("f4");
-    verify.completionListContains("e1");
-    verify.completionListContains("e2");
-    verify.not.completionListItemsCountIsGreaterThan(6);
-
-    goTo.marker(kind + "1");
-    verify.completionListContains("f1");
-    verify.completionListContains("f2");
-    verify.completionListContains("f3");
-    verify.completionListContains("f4");
-    verify.completionListContains("e1");
-    verify.completionListContains("e2");
-    verify.not.completionListItemsCountIsGreaterThan(6);
+    verify.completionListContains("f5");
+    verify.completionListContains("f6");
+    verify.completionListContains("g1");
+    verify.completionListContains("g2");
+    verify.not.completionListItemsCountIsGreaterThan(8);
+    }
 }
\ No newline at end of file
diff --git a/tests/cases/fourslash/completionForTripleSlashReference1.ts b/tests/cases/fourslash/completionForTripleSlashReference1.ts
deleted file mode 100644
index 2ce4de2e72e..00000000000
--- a/tests/cases/fourslash/completionForTripleSlashReference1.ts
+++ /dev/null
@@ -1,51 +0,0 @@
-/// <reference path='fourslash.ts' />
-
-// Should give completions for relative references to ts files when allowJs is false
-
-// @Filename: test0.ts
-//// /// <reference path="/*0*/
-//// /// <reference path="./*1*/
-//// /// <reference path="../*2*/
-//// /// <reference path=".//*3*/
-//// /// <reference path="./f/*4*/" />
-//// /// <reference path="./parentTest//*5*/
-
-// @Filename: parentTest/sub/test1.ts
-//// /// <reference path="../g/*6*/
-
-// @Filename: f1.ts
-//// /*f1*/
-// @Filename: f1.js
-//// /*f1j*/
-// @Filename: f1.d.ts
-//// /*f1d*/
-// @Filename: f2.tsx
-//// /f2*/
-// @Filename: f3.js
-//// /*f3*/
-// @Filename: f4.jsx
-//// /*f4*/
-// @Filename: e1.ts
-//// /*e1*/
-// @Filename: parentTest/g1.ts
-//// /*parentg1*/
-
-for (let i = 0; i < 5; i++) {
-    goTo.marker("" + i);
-    verify.completionListContains("f1.ts");
-    verify.completionListContains("f1.d.ts");
-    verify.completionListContains("f2.tsx");
-    verify.completionListContains("e1.ts");
-    verify.completionListContains("parentTest");
-    verify.not.completionListItemsCountIsGreaterThan(5);
-}
-
-goTo.marker("5");
-verify.completionListContains("g1.ts");
-verify.completionListContains("sub");
-verify.not.completionListItemsCountIsGreaterThan(2);
-
-goTo.marker("6");
-verify.completionListContains("g1.ts");
-verify.completionListContains("sub");
-verify.not.completionListItemsCountIsGreaterThan(2);
\ No newline at end of file
diff --git a/tests/cases/fourslash/completionForTripleSlashReference3.ts b/tests/cases/fourslash/tripleSlashRefPathCompletionAbsolutePaths.ts
similarity index 90%
rename from tests/cases/fourslash/completionForTripleSlashReference3.ts
rename to tests/cases/fourslash/tripleSlashRefPathCompletionAbsolutePaths.ts
index 798e556be58..99fffd7a7d6 100644
--- a/tests/cases/fourslash/completionForTripleSlashReference3.ts
+++ b/tests/cases/fourslash/tripleSlashRefPathCompletionAbsolutePaths.ts
@@ -1,6 +1,6 @@
 /// <reference path='fourslash.ts' />
 
-// Should give completions for absolute paths
+// Exercises completions for absolute paths.
 
 // @Filename: tests/test0.ts
 //// /// <reference path="/tests/cases/f/*0*/
diff --git a/tests/cases/fourslash/tripleSlashRefPathCompletionBackandForwardSlash.ts b/tests/cases/fourslash/tripleSlashRefPathCompletionBackandForwardSlash.ts
new file mode 100644
index 00000000000..2ec394e1dc8
--- /dev/null
+++ b/tests/cases/fourslash/tripleSlashRefPathCompletionBackandForwardSlash.ts
@@ -0,0 +1,70 @@
+/// <reference path='fourslash.ts' />
+
+// Exercises completions for hidden files (ie: those beginning with '.')
+
+// @Filename: f.ts
+//// /*f1*/
+// @Filename: d1/g.ts
+//// /*g1*/
+// @Filename: d1/d2/h.ts
+//// /*h1*/
+// @Filename: d1/d2/d3/i.ts
+//// /// <reference path=".\..\..\/*28*/
+
+// @Filename: test.ts
+//// /// <reference path="/*0*/
+//// /// <reference path=".//*1*/
+//// /// <reference path=".\/*2*/
+//// /// <reference path="./*3*/
+
+//// /// <reference path="d1//*4*/
+//// /// <reference path="d1/.//*5*/
+//// /// <reference path="d1/.\/*6*/
+//// /// <reference path="d1/./*7*/
+
+//// /// <reference path="d1\/*8*/
+//// /// <reference path="d1\.//*9*/
+//// /// <reference path="d1\.\/*10*/
+//// /// <reference path="d1\./*11*/
+
+//// /// <reference path="d1/d2//*12*/
+//// /// <reference path="d1/d2/.//*13*/
+//// /// <reference path="d1/d2/.\/*14*/
+//// /// <reference path="d1/d2/./*15*/
+
+//// /// <reference path="d1/d2\/*16*/
+//// /// <reference path="d1/d2\.//*17*/
+//// /// <reference path="d1/d2\.\/*18*/
+//// /// <reference path="d1/d2\./*19*/
+
+//// /// <reference path="d1\d2//*20*/
+//// /// <reference path="d1\d2/.//*21*/
+//// /// <reference path="d1\d2/.\/*22*/
+//// /// <reference path="d1\d2/./*23*/
+
+//// /// <reference path="d1\d2\/*24*/
+//// /// <reference path="d1\d2\.//*25*/
+//// /// <reference path="d1\d2\.\/*26*/
+//// /// <reference path="d1\d2\./*27*/
+
+testBlock(0,  'f.ts', "d1");
+testBlock(4,  'g.ts', "d2");
+testBlock(8,  'g.ts', "d2");
+testBlock(12, 'h.ts', "d3");
+testBlock(16, 'h.ts', "d3");
+testBlock(20, 'h.ts', "d3");
+testBlock(24, 'h.ts', "d3");
+
+goTo.marker("28");
+verify.completionListContains("g.ts");
+verify.completionListContains("d2");
+verify.not.completionListItemsCountIsGreaterThan(2);
+
+function testBlock(offset: number, fileName: string, dir: string) {
+    for (let m = offset; m < offset + 4; ++m) {
+        goTo.marker("" + m);
+        verify.completionListContains(fileName);
+        verify.completionListContains(dir);
+        verify.not.completionListItemsCountIsGreaterThan(2);
+    }
+}
diff --git a/tests/cases/fourslash/tripleSlashRefPathCompletionContext.ts b/tests/cases/fourslash/tripleSlashRefPathCompletionContext.ts
new file mode 100644
index 00000000000..ccab45a2b21
--- /dev/null
+++ b/tests/cases/fourslash/tripleSlashRefPathCompletionContext.ts
@@ -0,0 +1,21 @@
+/// <reference path='fourslash.ts' />
+
+// Exercises whether completions are supplied, conditional on the caret position in the ref comment.
+
+// @Filename: f.ts
+//// /*f*/
+
+// @Filename: test.ts
+//// /// <reference path/*0*/=/*1*/"/*8*/
+//// /// <reference path/*2*/=/*3*/"/*9*/"/*4*/ /*5*///*6*/>/*7*/
+
+for(let m = 0; m < 8; ++m) {
+    goTo.marker("" + m);
+    verify.not.completionListItemsCountIsGreaterThan(0);
+}
+
+for(let m of ["8", "9"]) {
+    goTo.marker(m);
+    verify.completionListContains("f.ts");
+    verify.not.completionListItemsCountIsGreaterThan(1);
+}
\ No newline at end of file
diff --git a/tests/cases/fourslash/tripleSlashRefPathCompletionExtensionsAllowJSFalse.ts b/tests/cases/fourslash/tripleSlashRefPathCompletionExtensionsAllowJSFalse.ts
new file mode 100644
index 00000000000..95a4cd01b60
--- /dev/null
+++ b/tests/cases/fourslash/tripleSlashRefPathCompletionExtensionsAllowJSFalse.ts
@@ -0,0 +1,31 @@
+/// <reference path='fourslash.ts' />
+
+// Should give completions for relative references to ts files only when allowJs is false.
+
+// @Filename: test0.ts
+//// /// <reference path="/*0*/
+//// /// <reference path=".//*1*/
+//// /// <reference path="./f/*2*/
+
+// @Filename: f1.ts
+//// /*f1*/
+// @Filename: f1.js
+//// /*f1j*/
+// @Filename: f1.d.ts
+//// /*f1d*/
+// @Filename: f1.tsx
+//// /f2*/
+// @Filename: f1.js
+//// /*f3*/
+// @Filename: f1.jsx
+//// /*f4*/
+// @Filename: f1.cs
+//// /*f5*/
+
+for (let i = 0; i < 3; i++) {
+    goTo.marker("" + i);
+    verify.completionListContains("f1.ts");
+    verify.completionListContains("f1.d.ts");
+    verify.completionListContains("f1.tsx");
+    verify.not.completionListItemsCountIsGreaterThan(3);
+}
\ No newline at end of file
diff --git a/tests/cases/fourslash/completionForTripleSlashReference2.ts b/tests/cases/fourslash/tripleSlashRefPathCompletionExtensionsAllowJSTrue.ts
similarity index 53%
rename from tests/cases/fourslash/completionForTripleSlashReference2.ts
rename to tests/cases/fourslash/tripleSlashRefPathCompletionExtensionsAllowJSTrue.ts
index e6553ce8e73..e8fe415824b 100644
--- a/tests/cases/fourslash/completionForTripleSlashReference2.ts
+++ b/tests/cases/fourslash/tripleSlashRefPathCompletionExtensionsAllowJSTrue.ts
@@ -1,15 +1,13 @@
 /// <reference path='fourslash.ts' />
 
-// Should give completions for relative references to js and ts files when allowJs is true
+// Should give completions for relative references to ts and js files when allowJs is true.
 
 // @allowJs: true
 
 // @Filename: test0.ts
 //// /// <reference path="/*0*/
-//// /// <reference path="./*1*/
-//// /// <reference path="../*2*/
-//// /// <reference path=".//*3*/
-//// /// <reference path="./f/*4*/" />
+//// /// <reference path=".//*1*/
+//// /// <reference path="./f/*2*/
 
 // @Filename: f1.ts
 //// /*f1*/
@@ -17,17 +15,21 @@
 //// /*f1j*/
 // @Filename: f1.d.ts
 //// /*f1d*/
-// @Filename: f2.tsx
+// @Filename: f1.tsx
 //// /f2*/
-// @Filename: f4.jsx
+// @Filename: f1.js
+//// /*f3*/
+// @Filename: f1.jsx
 //// /*f4*/
+// @Filename: f1.cs
+//// /*f5*/
 
-for (let i = 0; i < 5; i++) {
+for (let i = 0; i < 3; i++) {
     goTo.marker("" + i);
     verify.completionListContains("f1.ts");
-    verify.completionListContains("f1.js");
     verify.completionListContains("f1.d.ts");
-    verify.completionListContains("f2.tsx");
-    verify.completionListContains("f4.jsx");
+    verify.completionListContains("f1.tsx");
+    verify.completionListContains("f1.js");
+    verify.completionListContains("f1.jsx");
     verify.not.completionListItemsCountIsGreaterThan(5);
 }
\ No newline at end of file
diff --git a/tests/cases/fourslash/tripleSlashRefPathCompletionHiddenFile.ts b/tests/cases/fourslash/tripleSlashRefPathCompletionHiddenFile.ts
new file mode 100644
index 00000000000..fffd310bfeb
--- /dev/null
+++ b/tests/cases/fourslash/tripleSlashRefPathCompletionHiddenFile.ts
@@ -0,0 +1,20 @@
+/// <reference path='fourslash.ts' />
+
+// Exercises completions for hidden files (ie: those beginning with '.')
+
+// @Filename: f.ts
+//// /*f*/
+// @Filename: .hidden.ts
+//// /*hidden*/
+
+// @Filename: test.ts
+//// /// <reference path="/*0*/
+//// /// <reference path="./*1*/
+//// /// <reference path=".//*2*/
+//// /// <reference path=".\/*3*/
+
+for(let m of ["0", "1", "2", "3"]) {
+    goTo.marker(m);
+    verify.completionListContains("f.ts");
+    verify.not.completionListItemsCountIsGreaterThan(1);
+}
\ No newline at end of file
diff --git a/tests/cases/fourslash/tripleSlashRefPathCompletionNarrowing.ts b/tests/cases/fourslash/tripleSlashRefPathCompletionNarrowing.ts
new file mode 100644
index 00000000000..6bf3a1e72e3
--- /dev/null
+++ b/tests/cases/fourslash/tripleSlashRefPathCompletionNarrowing.ts
@@ -0,0 +1,34 @@
+/// <reference path='fourslash.ts' />
+
+// Exercises how changes in the basename change the completions offered.
+// They should have no effect, as filtering completions is the responsibility of the editor.
+
+// @Filename: f1.ts
+//// /*f1*/
+// @Filename: f2.ts
+//// /*f2*/
+// @Filename: d/g.ts
+//// /*g*/
+
+// @Filename: test.ts
+//// /// <reference path="f/*0*/
+//// /// <reference path="./f/*1*/
+
+//// /// <reference path="./d/*2*/
+
+//// /// <reference path="f1/*3*/
+//// /// <reference path="f1./*4*/
+//// /// <reference path="f1.t/*5*/
+//// /// <reference path="f1.ts/*6*/
+//// /// <reference path="./f1/*7*/
+//// /// <reference path="./f1./*8*/
+//// /// <reference path="./f1.t/*9*/
+//// /// <reference path="./f1.ts/*10*/
+
+for (let m = 0; m < 11; ++m) {
+    goTo.marker("" + m);
+    verify.completionListContains("f1.ts");
+    verify.completionListContains("f2.ts");
+    verify.completionListContains("d");
+    verify.not.completionListItemsCountIsGreaterThan(3);
+}
\ No newline at end of file
diff --git a/tests/cases/fourslash/tripleSlashRefPathCompletionRelativePaths.ts b/tests/cases/fourslash/tripleSlashRefPathCompletionRelativePaths.ts
new file mode 100644
index 00000000000..ba6af8735f8
--- /dev/null
+++ b/tests/cases/fourslash/tripleSlashRefPathCompletionRelativePaths.ts
@@ -0,0 +1,77 @@
+/// <reference path='fourslash.ts' />
+
+// Exercises relative path completions going up and down 2 directories
+// and the use of forward- and back-slashes and combinations thereof.
+
+// @Filename: f.ts
+//// /*f1*/
+// @Filename: d1/g.ts
+//// /*g1*/
+// @Filename: d1/d2/h.ts
+//// /*h1*/
+// @Filename: d1/d2/d3/i.ts
+//// /*i1*/
+// @Filename: d1/d2/d3/d4/j.ts
+//// /*j1*/
+
+// @Filename: d1/d2/test.ts
+//// /// <reference path="/*0*/
+//// /// <reference path=".//*1*/
+//// /// <reference path="./*2*/
+//// /// <reference path="../*3*/
+//// /// <reference path="d3/*4*/
+
+//// /// <reference path="..//*5*/
+//// /// <reference path="..\/*6*/
+
+//// /// <reference path="../..//*7*/
+
+//// /// <reference path="d3//*8*/
+//// /// <reference path="./d3//*9*/
+
+//// /// <reference path="d3/d4//*10*/
+//// /// <reference path="./d3/d4//*11*/
+
+workingDirCompletions();
+parentDirCompletions();
+childDirCompletions();
+
+function workingDirCompletions() {
+    for (let m = 0; m < 5; ++m) {
+        goTo.marker("" + m);
+        verify.completionListContains("h.ts");
+        verify.completionListContains("d3");
+        verify.not.completionListItemsCountIsGreaterThan(2);
+    }
+}
+
+function parentDirCompletions() {
+
+    for (let m of ["5", "6"]) {
+        goTo.marker(m);
+        verify.completionListContains("g.ts");
+        verify.completionListContains("d2");
+        verify.not.completionListItemsCountIsGreaterThan(2);
+    }
+
+    goTo.marker("7");
+    verify.completionListContains("f.ts");
+    verify.completionListContains("d1");
+    verify.not.completionListItemsCountIsGreaterThan(2);
+}
+
+function childDirCompletions() {
+
+    for (let m of ["8", "9"]) {
+        goTo.marker(m);
+        verify.completionListContains("i.ts");
+        verify.completionListContains("d4");
+        verify.not.completionListItemsCountIsGreaterThan(2);
+    }
+
+    for (let m of ["10", "11"]) {
+        goTo.marker(m);
+        verify.completionListContains("j.ts");
+        verify.not.completionListItemsCountIsGreaterThan(1);
+    }
+}
\ No newline at end of file
diff --git a/tests/cases/fourslash/completionForTripleSlashReference4.ts b/tests/cases/fourslash/tripleSlashRefPathCompletionRootdirs.ts
similarity index 100%
rename from tests/cases/fourslash/completionForTripleSlashReference4.ts
rename to tests/cases/fourslash/tripleSlashRefPathCompletionRootdirs.ts