Added tests for syntactic context.

tests/cases/fourslash/signatureHelpFilteredTriggers02.ts

@@ -0,0 +1,36 @@
+/// <reference path="fourslash.ts" />
+
+////function foo<T>(x: T): T {
+////  throw null;
+////}
+////
+////foo(/*1*/"");
+////foo(` ${100/*2*/}`);
+////foo(/*3*/);
+////foo(100 /*4*/)
+////foo([/*5*/])
+////foo({ hello: "hello"/*6*/})
+
+const charMap = {
+    1: "(",
+    2: ",",
+    3: "(",
+    4: "<",
+    5: ",",
+    6: ",",
+}
+
+for (const markerName of Object.keys(charMap)) {
+    const triggerCharacter = charMap[markerName];
+    goTo.marker(markerName);
+    edit.insert(triggerCharacter);
+    verify.noSignatureHelpForTriggerReason({
+        kind: "characterTyped",
+        triggerCharacter,
+    });
+    verify.signatureHelpPresentForTriggerReason({
+        kind: "retrigger",
+        triggerCharacter,
+    });
+    edit.backspace(triggerCharacter.length);
+}

tests/cases/fourslash/signatureHelpFilteredTriggers03.ts

@@ -0,0 +1,23 @@
+/// <reference path="fourslash.ts" />
+
+////declare class ViewJayEss {
+////    constructor(obj: object);
+////}
+////new ViewJayEss({
+////    methods: {
+////        sayHello/**/
+////    }
+////});
+
+goTo.marker();
+edit.insert("(");
+verify.noSignatureHelpForTriggerReason({
+    kind: "characterTyped",
+    triggerCharacter: "(",
+});
+
+edit.insert(") {},");
+verify.noSignatureHelpForTriggerReason({
+    kind: "characterTyped",
+    triggerCharacter: ",",
+});

tests/cases/fourslash/signatureHelpWithTriggers01.ts

@@ -0,0 +1,31 @@
+/// <reference path="fourslash.ts" />
+
+////declare function foo<T>(x: T, y: T): T;
+////
+////foo/*1*//*2*/;
+////foo(/*3*/100/*4*/);
+////foo/*5*//*6*/();
+
+const charMap = {
+    1: "(",
+    2: "<",
+    3: ",",
+    4: ",",
+    5: "(",
+    6: "<",
+}
+
+for (const markerName of Object.keys(charMap)) {
+    const triggerCharacter = charMap[markerName];
+    goTo.marker(markerName);
+    edit.insert(triggerCharacter);
+    verify.signatureHelpPresentForTriggerReason({
+        kind: "characterTyped",
+        triggerCharacter,
+    });
+    verify.signatureHelpPresentForTriggerReason({
+        kind: "retrigger",
+        triggerCharacter,
+    });
+    edit.backspace(triggerCharacter.length);
+}

tests/cases/fourslash/signatureHelpWithTriggers02.ts

@@ -0,0 +1,38 @@
+/// <reference path="fourslash.ts" />
+
+////declare function foo<T>(x: T, y: T): T;
+////declare function bar<U>(x: U, y: U): U;
+////
+////foo(bar/*1*/)
+
+goTo.marker("1");
+
+edit.insert("(");
+verify.signatureHelp({
+    text: "bar<U>(x: U, y: U): U",
+    triggerReason: {
+        kind: "characterTyped",
+        triggerCharacter: "(",
+    }
+});
+edit.backspace();
+
+edit.insert("<");
+verify.signatureHelp({
+    text: "bar<U>(x: U, y: U): U",
+    triggerReason: {
+        kind: "characterTyped",
+        triggerCharacter: "(",
+    }
+});
+edit.backspace();
+
+edit.insert(",");
+verify.signatureHelp({
+    text: "foo(x: <U>(x: U, y: U) => U, y: <U>(x: U, y: U) => U): <U>(x: U, y: U) => U",
+    triggerReason: {
+        kind: "characterTyped",
+        triggerCharacter: "(",
+    }
+});
+edit.backspace();