Fix #130 Stop resolving definitions after the line

If a build stage name shadows an actual image that was used previously,
trying to resolve the definition of the actual name should not end up
jumping forward to the build stage name.

Signed-off-by: Remy Suen <remy.suen@docker.com>

CHANGELOG.md

@@ -5,6 +5,9 @@ All notable changes to this project will be documented in this file.
 ### Added
 - support preparing renames for here-documents ([#129](https://github.com/rcjsuen/dockerfile-language-service/issues/129))
 
+### Fixed
+- stop resolving definitions to build stages after the selected line ([#130](https://github.com/rcjsuen/dockerfile-language-service/issues/130))
+
 ## [0.14.0] - 2024-06-18
 ### Added
 - support computing highlight ranges for heredocs ([#121](https://github.com/rcjsuen/dockerfile-language-service/issues/121))

src/dockerDefinition.ts

@@ -42,7 +42,7 @@ export class DockerDefinition {
             if (Util.isInsideRange(position, range)) {
                 const stageName = instruction.getImageName();
                 for (const from of dockerfile.getFROMs()) {
-                    if (stageName === from.getBuildStage()) {
+                    if (stageName === from.getBuildStage() && from.getRange().start.line < range.start.line) {
                         return from.getBuildStageRange();
                     }
                 }

test/dockerDefinition.test.ts

@@ -120,6 +120,26 @@ describe("Dockerfile Document Definition tests", function () {
                 let location = computeDefinition(document, Position.create(1, 10));
                 assert.strictEqual(location, null);
             });
+
+            describe("stage name shadowing an image", () => {
+                it("referencing a later stage", () => {
+                    const document = "FROM alpine\nFROM scratch AS alpine";
+                    let location = computeDefinition(document, Position.create(0, 8));
+                    assert.strictEqual(location, null);
+
+                    location = computeDefinition(document, Position.create(1, 19));
+                    assertLocation(location, 1, 16, 1, 22);
+                });
+
+                it("referencing itself", () => {
+                    const document = "FROM alpine AS alpine";
+                    let location = computeDefinition(document, Position.create(0, 8));
+                    assert.strictEqual(location, null);
+
+                    location = computeDefinition(document, Position.create(0, 18));
+                    assertLocation(location, 0, 15, 0, 21);
+                });
+            });
         });
     });