Autocomplete: Add php, dart, and vue support for multi-line completio…

…ns (#533)

Looking at some language specific metrics it seems like we have a lot of
users for these languages. Let's make their experience better 😎

## Test plan

Added a test case

<!-- Required. See
https://docs.sourcegraph.com/dev/background-information/testing_principles.
-->

vscode/src/completions/language.ts

@@ -10,12 +10,15 @@ export function getLanguageConfig(languageId: string): LanguageConfig | null {
         case 'c':
         case 'cpp':
         case 'csharp':
+        case 'dart':
         case 'go':
         case 'java':
         case 'javascript':
         case 'javascriptreact':
+        case 'php':
         case 'typescript':
         case 'typescriptreact':
+        case 'vue':
             return {
                 blockStart: '{',
                 blockElseTest: /^[\t ]*} else/,

vscode/src/completions/vscodeInlineCompletionItemProvider.test.ts

@@ -615,6 +615,78 @@ describe('Cody completions', () => {
             `)
         })
 
+        it('works with php', async () => {
+            const { completions, requests } = await complete(
+                dedent`
+                    for ($i = 0; $i < 11; $i++) {
+                        if ($i % 2 == 0) {
+                            █
+                `,
+                [
+                    completion`
+                            ├echo $i;
+                        } else if ($i % 3 == 0) {
+                            echo "Multiple of 3: " . $i;
+                        } else {
+                            echo "ODD " . $i;
+                        }
+                    }
+
+                    for ($i = 0; $i < 12; $i++) {
+                        echo "unrelated";
+                    }┤`,
+                ],
+                'c'
+            )
+
+            expect(requests).toHaveLength(3)
+            expect(requests[0].stopSequences).not.toContain('\n')
+            expect(completions[0].insertText).toMatchInlineSnapshot(`
+              "echo $i;
+                  } else if ($i % 3 == 0) {
+                      echo \\"Multiple of 3: \\" . $i;
+                  } else {
+                      echo \\"ODD \\" . $i;
+                  }"
+            `)
+        })
+
+        it('works with dart', async () => {
+            const { completions, requests } = await complete(
+                dedent`
+                    for (int i = 0; i < 11; i++) {
+                        if (i % 2 == 0) {
+                            █
+                `,
+                [
+                    completion`
+                            ├print(i);
+                        } else if (i % 3 == 0) {
+                          print('Multiple of 3: $i');
+                        } else {
+                          print('ODD $i');
+                        }
+                      }
+
+                      for (int i = 0; i < 12; i++) {
+                        print('unrelated');
+                      }┤`,
+                ],
+                'dart'
+            )
+
+            expect(requests).toHaveLength(3)
+            expect(requests[0].stopSequences).not.toContain('\n')
+            expect(completions[0].insertText).toMatchInlineSnapshot(`
+              "print(i);
+                  } else if (i % 3 == 0) {
+                      print('Multiple of 3: $i');
+                  } else {
+                      print('ODD $i');
+                  }"
+            `)
+        })
+
         it('skips over empty lines', async () => {
             const { completions } = await complete(
                 dedent`