Analyzer should report "unnecessary" and "redundant" imports #44569

srawlins · 2020-12-30T03:40:13Z

The analyzer should report when a library uses some elements which are provided by more than one import directive (with the same prefix).

If any such import directive provides fewer elements which are used by the library than any of the other relevant imports, then that import directive is unnecessary. Removing each unnecessary import is strictly safe.

If any such import directive provides the exact same elements which are used by the library as one or more of the other relevant imports, then it is redundant. Removing one redundant import is strictly safe, but removing all redundant imports is not safe, and the analyzer should use a heuristic to decide what action to recommend.

Examples:

Simple unnecessary import

import 'one.dart' show A, B;
import 'two.dart' show A;
A? a;
B? b;

The import of two.dart is unnecessary.

Simple redundant import

import 'one.dart' show A;
import 'two.dart' show A;
A? a;

Each import is redundant; neither is unnecessary.

More interesting unnecessary imports

import 'one.dart' show A;
import 'two.dart' show A, B;
import 'three.dart' show A, B, C;
A? a;
B? b;
C? c;

The imports of one.dart and two.dart are unnecessary.

More interesting redundant imports

import 'one.dart' show A, B;
import 'two.dart' show A, C;
import 'three.dart' show B, C;
A? a;
B? b;
C? c;

Each of the three imports is redundant, but ultimately, only one can be safely removed.

The text was updated successfully, but these errors were encountered:

#44569 Change-Id: I0b5d237f532ab99c112247e9f24392ef317575dd Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/177222 Reviewed-by: Konstantin Shcheglov <scheglov@google.com> Commit-Queue: Samuel Rawlins <srawlins@google.com>

TEST=Existing tests on existing bots Bug: #44569 Change-Id: I0c8ee9afa85da3a1a39a983841e62956e76dd509 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/177242 Commit-Queue: Samuel Rawlins <srawlins@google.com> Reviewed-by: Johnni Winther <johnniwinther@google.com>

Bug: #44569 Change-Id: I75ca15c391e0c77840e65d27b26583f15b59eea4 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/177340 Reviewed-by: Konstantin Shcheglov <scheglov@google.com> Commit-Queue: Samuel Rawlins <srawlins@google.com>

Bug: #44569 Change-Id: I621f187a7ec654235b21a77f28258bba7ef8c179 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/177300 Reviewed-by: Konstantin Shcheglov <scheglov@google.com> Commit-Queue: Samuel Rawlins <srawlins@google.com>

In each library where an import is removed, the library uses some elements provided by the import, BUT there is another import which provides all of the same elements, and at least one more which the library uses. In this CL, we remove the imports which can be simply removed in favor of the other already present imports. See dart-lang/sdk#44569 for more information.

In each library where an import is removed, the library uses some elements provided by the import, BUT there is another import which provides all of the same elements, and at least one more which the library uses. In this change, we remove the imports which can be simply removed in favor of the other already present imports. See dart-lang/sdk#44569 for more information.

Bug: #44569 Change-Id: Icad2908772eb42593c0149a99b8256d470490670 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/177241 Reviewed-by: Sigmund Cherem <sigmund@google.com> Reviewed-by: Nicholas Shahan <nshahan@google.com> Commit-Queue: Samuel Rawlins <srawlins@google.com>

In each library where an import is removed, the library uses some elements provided by the import, BUT there is another import which provides all of the same elements, and at least one more which the library uses. In this change, we remove the imports which can be simply removed in favor of the other already present imports. See dart-lang/sdk#44569 for more information.

Bug: #44569 Change-Id: Ied7a1ed105ac82cf9e0f38454bce8cb4a69e17e7 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/212605 Auto-Submit: Samuel Rawlins <srawlins@google.com> Commit-Queue: Brian Wilkerson <brianwilkerson@google.com> Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>

Bug: #44569 Change-Id: I92e93777ee4f62e82f179338475828edeaac15dd Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/212608 Auto-Submit: Samuel Rawlins <srawlins@google.com> Commit-Queue: Johnni Winther <johnniwinther@google.com> Reviewed-by: Johnni Winther <johnniwinther@google.com>

Bug: #44569 Change-Id: I847603b5a1debb55b5c78e0d837ebcfa2d133d77 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/212607 Auto-Submit: Samuel Rawlins <srawlins@google.com> Commit-Queue: Paul Berry <paulberry@google.com> Reviewed-by: Paul Berry <paulberry@google.com>

TEST=N/A Bug: #44569 Change-Id: I61adbdb6666fee9f34372a83d4c3383b636f76e9 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/212606 Auto-Submit: Samuel Rawlins <srawlins@google.com> Commit-Queue: Samuel Rawlins <srawlins@google.com> Reviewed-by: Ben Konyi <bkonyi@google.com>

In each library where an import is removed, the library uses some elements provided by the import, BUT there is another import which provides all of the same elements, and at least one more which the library uses. In this change, we remove the imports which can be simply removed in favor of the other already present imports. See dart-lang/sdk#44569 for more information.

In each library where an import is removed, the library uses some elements provided by the import, BUT there is another import which provides all of the same elements, and at least one more which the library uses. In this change, we remove the imports which can be simply removed in favor of the other already present imports. Additionally, I add an ignore to analysis_options.yaml, so that unnecessary_import can land in Dart. After it lands, we can clean up the remaining cases in flutter. See dart-lang/sdk#44569 for more information.

Bug: #44569 Change-Id: I646f5994b40f2007f8d8d4b5ef35e2c9ffbd2376 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/213423 Auto-Submit: Samuel Rawlins <srawlins@google.com> Reviewed-by: Johnni Winther <johnniwinther@google.com> Commit-Queue: Johnni Winther <johnniwinther@google.com>

Bug: #44569 Change-Id: I98e103a1af11794927fc1fe6794e69ec655debf6 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/213424 Auto-Submit: Samuel Rawlins <srawlins@google.com> Commit-Queue: Mayank Patke <fishythefish@google.com> Reviewed-by: Mayank Patke <fishythefish@google.com>

Many of these are a redundancy between 'package:analyzer/src/generated/source.dart' and 'package:analyzer/src/generated/source_io.dart' I chose to remove the latter, for no particular reason. Bug: #44569 Change-Id: Ic69b09fd502c978cef9e4d3b8a0ef9acd92d5184 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/213849 Reviewed-by: Brian Wilkerson <brianwilkerson@google.com> Commit-Queue: Samuel Rawlins <srawlins@google.com>

Each of these imports removed is redundant with 'package:kernel/ast.dart'. Bug: #44569 Change-Id: Ia9bc08b4ffd863572c84fe8a4fa465d2e8e04f7c Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/213845 Reviewed-by: Jens Johansen <jensj@google.com> Commit-Queue: Samuel Rawlins <srawlins@google.com>

Very often there were two imports of the same URI, one of which also had a `show` combinator. I opted to remove the other one. Bug: #44569 Change-Id: I1263c892f94f0645fda6dee371dfc1fcddcd2344 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/213846 Reviewed-by: Johnni Winther <johnniwinther@google.com> Commit-Queue: Samuel Rawlins <srawlins@google.com>

Bug: #44569 Change-Id: Iab83d15b0f6c5448b75881fcba8c8ea177feab71 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/213852 Auto-Submit: Samuel Rawlins <srawlins@google.com> Commit-Queue: Nicholas Shahan <nshahan@google.com> Reviewed-by: Nicholas Shahan <nshahan@google.com>

Bug: #44569 Change-Id: I6fa385eddc76397ce4944674bd548a16755f265d Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/213850 Auto-Submit: Samuel Rawlins <srawlins@google.com> Commit-Queue: Riley Porter <rileyporter@google.com> Reviewed-by: Riley Porter <rileyporter@google.com>

In many files, there is a redundancy in importing import 'package:compiler/src/common.dart' and import 'package:compiler/src/diagnostics/diagnostic_listener.dart' I chose to remove the latter import. Bug: #44569 Change-Id: Ia6c871080bf2d7c637694a4fe5cb1b84e540b789 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/213851 Reviewed-by: Mayank Patke <fishythefish@google.com> Commit-Queue: Samuel Rawlins <srawlins@google.com>

kevmoo · 2021-10-15T20:01:21Z

@srawlins – can we close this?

srawlins · 2021-10-15T22:46:00Z

We're not reporting redundant imports yet.

kevmoo · 2021-10-15T23:53:59Z

I've been seeing it all over with the latest dev release!

…

On Fri, Oct 15, 2021 at 3:46 PM Sam Rawlins ***@***.***> wrote: We're not reporting redundant imports yet. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#44569 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAAEFCXDS7MIWFHGL336FVLUHCVLHANCNFSM4VN4EAKQ> .

srawlins · 2021-10-15T23:54:58Z

Those should just be unnecessary imports.

In each library where an import is removed, the library uses some elements provided by the import, BUT there is another import which provides all of the same elements, and at least one more which the library uses. In this change, we remove the imports which can be simply removed in favor of the other already present imports. See dart-lang/sdk#44569 for more information.

srawlins added area-analyzer Use area-analyzer for Dart analyzer issues, including the analysis server and code completion. P3 A lower priority bug or feature request analyzer-warning Issues with the analyzer's Warning codes labels Dec 30, 2020

srawlins self-assigned this Dec 30, 2020

srawlins mentioned this issue Dec 30, 2020

Remove unnecessary import sass/dart-sass#1177

Merged

srawlins mentioned this issue Jan 5, 2021

Remove "unnecessary" imports in flutter/src/services flutter/flutter#73340

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13 tasks

srawlins mentioned this issue Jan 5, 2021

Remove "unnecessary" imports. flutter/flutter#73344

Merged

13 tasks

srawlins mentioned this issue Jan 5, 2021

Remove "unnecessary" imports in flutter/src/rendering flutter/flutter#73368

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13 tasks

srawlins mentioned this issue Jan 6, 2021

Remove "unnecessary" imports from flutter/src/gestures flutter/flutter#73389

Merged

13 tasks

srawlins mentioned this issue Jan 7, 2021

Remove "unnecessary" imports in flutter/src/cupertino flutter/flutter#73486

Merged

13 tasks

srawlins mentioned this issue Jan 7, 2021

Remove "unnecessary" import in flutter_tools flutter/flutter#73488

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13 tasks

srawlins mentioned this issue Jan 21, 2021

Remove unnecessary imports in dev/benchmarks flutter/flutter#74382

Merged

8 tasks

This was referenced Jul 1, 2021

Remove "unnecessary" imports. flutter/flutter#85736

Merged

Remove "unnecessary" imports. flutter/engine#27131

Closed

pq mentioned this issue Jul 7, 2021

unused import dart-lang/linter#2758

Closed

srawlins mentioned this issue Sep 9, 2021

Remove "unnecessary" imports from packages/ flutter/flutter#89795

Merged

8 tasks

srawlins mentioned this issue Sep 9, 2021

Remove and also ignore unnecessary imports flutter/flutter#89796

Merged

8 tasks

srawlins mentioned this issue Mar 29, 2022

Analyzer doesn't give unnecessary_import feedback if element used only from 1 export #48038

Closed

This was referenced Jul 21, 2022

unnecessary_import hint is not reported if the same number of elements are used from each file #49497

Closed

unnecessary_import hint is not reported with single element import #49505

Closed

srawlins added the type-enhancement A request for a change that isn't a bug label Mar 13, 2024

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Analyzer should report "unnecessary" and "redundant" imports #44569

Analyzer should report "unnecessary" and "redundant" imports #44569

srawlins commented Dec 30, 2020

kevmoo commented Oct 15, 2021

srawlins commented Oct 15, 2021

kevmoo commented Oct 15, 2021 via email

srawlins commented Oct 15, 2021

Analyzer should report "unnecessary" and "redundant" imports #44569

Analyzer should report "unnecessary" and "redundant" imports #44569

Comments

srawlins commented Dec 30, 2020

Simple unnecessary import

Simple redundant import

More interesting unnecessary imports

More interesting redundant imports

kevmoo commented Oct 15, 2021

srawlins commented Oct 15, 2021

kevmoo commented Oct 15, 2021 via email

srawlins commented Oct 15, 2021