fix(graphql-language-service): fix off by one on hover

[bensengupta]

Hey, thanks for making this! This PR fixes a small off-by-one issue when hovering.

Details

I am using graphql-language-service-cli in Neovim. The issue is illustrated below:

Hover, no information (incorrect, should show info)

Hover, shows information (correct)

Hover, shows information (incorrect, should not show info)

Hover, no information (correct)

[changeset-bot]

🦋 Changeset detected

Latest commit: b7e0a66

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
graphql-language-service	Patch
codemirror-graphql	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: bensengupta / name: Benjamin Sengupta (f396fa9, e55cfea, fbb4e5e, b7e0a66)

[bensengupta]

Seems like there is a race condition in the tests. Am unable to reproduce test failure locally.

Maybe replace this

graphiql/packages/graphql-language-service-server/src/MessageProcessor.ts

Lines 142 to 144 in b495159

	if (!existsSync(this._tmpDirBase)) {
	void mkdirSync(this._tmpDirBase);
	}

with this?

    try {
      void mkdirSync(this._tmpDirBase);
    } catch (err) {
      if (err instanceof Error && 'code' in err && err.code === 'EEXIST') {
        return;
      }
      throw err;
    }

[bensengupta]

Just to explain this change: getContextAtPosition is used in 2 places:

In getHoverInformation, the offset needs to be changed to 0 to fix the off-by-one problem on hover.

graphiql/packages/graphql-language-service/src/interface/getHoverInformation.ts

Line 39 in b495159

const context = getContextAtPosition(queryText, cursor, schema, contextToken);

In getAutocompleteSuggestions, the offset needs to be kept at 1 as the current behavior is correct.

graphiql/packages/graphql-language-service/src/interface/getAutocompleteSuggestions.ts

Lines 145 to 152 in b7e0a66

	const context = getContextAtPosition(
	queryText,
	cursor,
	schema,
	contextToken,
	options,
	1,
	);

[bensengupta]

Hey @acao @dimaMachina, any chance one of you could have a look?