feat(firestore): Add ifNull and coalesce expressions

[milaGGL]

Add support for ifNull and coalesce.

[changeset-bot]

🦋 Changeset detected

Latest commit: 2b30319

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

This PR includes changesets to release 3 packages

Name	Type
firebase	Minor
@firebase/firestore	Minor
@firebase/firestore-compat	Patch

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[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request significantly enhances Firestore's data manipulation capabilities by introducing two new pipeline expressions: ifNull and coalesce. These additions provide developers with more powerful and flexible tools for handling null or absent values directly within their queries, streamlining data processing and reducing the need for client-side logic. The changes involve updates to the core expression logic, API definitions, documentation, and test suites to ensure full functionality and clarity.

Highlights

• New Pipeline Expressions: Added support for ifNull and coalesce pipeline expressions in Firestore, providing more robust null handling capabilities.
• API Surface Expansion: Introduced new API declarations for ifNull and coalesce functions and Expression methods across both Firestore and Firestore Lite.
• Documentation Updates: Updated developer documentation and API review files to reflect the new ifNull and coalesce expressions, including usage examples.
• Test Coverage: Included comprehensive integration and unit tests to validate the functionality of the new ifNull and coalesce expressions.

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[gemini-code-assist]

Code Review

This pull request introduces support for new pipeline expressions, ifNull and coalesce, in Firebase Firestore and Firestore Lite. The changes include adding API definitions, implementing the expressions in the Expression class, updating documentation, and adding integration tests. Feedback from the review primarily focuses on documentation improvements, such as correcting capitalization inconsistencies, fixing formatting errors with [Expression] links, and ensuring descriptions accurately reflect that ifNull and coalesce handle both null and absent values.

I am having trouble creating individual review comments. Click here to see my feedback.

docs-devsite/firestore_lite_pipelines.expression.md (81)

There's a capitalization inconsistency in the description. "Returns" should be in lowercase to be consistent with other descriptions in this file.

|  [coalesce(replacement, others)](./firestore_lite_pipelines.expression.md#expressioncoalesce) |  | <b><i>(Public Preview)</i></b> Creates an expression that returns the first non-null, non-absent argument, without evaluating the rest of the arguments. When all arguments are null or absent, returns the last argument. |

docs-devsite/firestore_lite_pipelines.expression.md (1513)

There's a capitalization inconsistency in the description. "Returns" should be in lowercase to be consistent with standard documentation style.

Creates an expression that returns the first non-null, non-absent argument, without evaluating the rest of the arguments. When all arguments are null or absent, returns the last argument.

docs-devsite/firestore_lite_pipelines.expression.md (2599)

There's a formatting error in the documentation. The backslash before [Expression] should be removed to correctly render the link.

A new [Expression] representing the ifNull operation.

docs-devsite/firestore_lite_pipelines.expression.md (2633)

There's a formatting error in the documentation. The backslash before [Expression] should be removed to correctly render the link.

A new [Expression] representing the ifNull operation.

docs-devsite/firestore_lite_pipelines.md (95)

There's a capitalization inconsistency in the description. "Returns" should be in lowercase to be consistent with other descriptions in this file.

|  [coalesce(expression, replacement, others)](./firestore_lite_pipelines.md#coalesce_00859cb) | <b><i>(Public Preview)</i></b> Creates an expression that returns the first non-null, non-absent argument, without evaluating the rest of the arguments. When all arguments are null or absent, returns the last argument. |

docs-devsite/firestore_lite_pipelines.md (174)

There's a capitalization inconsistency in the description. "Returns" should be in lowercase to be consistent with other descriptions in this file.

|  [coalesce(fieldName, replacement, others)](./firestore_lite_pipelines.md#coalesce_249958e) | <b><i>(Public Preview)</i></b> Creates an expression that returns the first non-null, non-absent argument, without evaluating the rest of the arguments. When all arguments are null or absent, returns the last argument. |

docs-devsite/firestore_lite_pipelines.md (290-291)

The description for ifNull is incomplete. It should mention that it also checks for absent values, not just null values, to be consistent with the implementation and other parts of the documentation.

|  [ifNull(ifExpr, elseExpr)](./firestore_lite_pipelines.md#ifnull_0e6d161) | <b><i>(Public Preview)</i></b> Creates an expression that returns the <code>elseExpr</code> argument if <code>ifExpr</code> is null or absent, else return the result of the <code>ifExpr</code> argument evaluation. |
|  [ifNull(ifExpr, elseValue)](./firestore_lite_pipelines.md#ifnull_c34e5ed) | <b><i>(Public Preview)</i></b> Creates an expression that returns the <code>elseValue</code> argument if <code>ifExpr</code> is null or absent, else return the result of the <code>ifExpr</code> argument evaluation. |

docs-devsite/firestore_lite_pipelines.md (2637)

There's a capitalization inconsistency in the description. "Returns" should be in lowercase to be consistent with standard documentation style.

Creates an expression that returns the first non-null, non-absent argument, without evaluating the rest of the arguments. When all arguments are null or absent, returns the last argument.

docs-devsite/firestore_lite_pipelines.md (9189)

The description for ifNull is incomplete. It should mention that it also checks for absent values, not just null values, to be consistent with the implementation.

Creates an expression that returns the `elseExpr` argument if `ifExpr` is null or absent, else return the result of the `ifExpr` argument evaluation.

docs-devsite/firestore_lite_pipelines.md (9236)

The description for the ifExpr parameter is inconsistent. It should state that it checks for "null or absence" to be accurate.

|  ifExpr | [Expression](./firestore_lite_pipelines.expression.md#expression_class) | The expression to check for null or absence. |

docs-devsite/firestore_lite_pipelines.md (9243)

There's a formatting error in the documentation. The backslash before [Expression] should be removed to correctly render the link.

A new [Expression] representing the ifNull operation.

docs-devsite/firestore_lite_pipelines.md (9381)

There's a formatting error in the documentation. The backslash before [ifFieldName] should be removed to correctly render the link.

|  elseValue | unknown | The value that will be returned if [ifFieldName] is null or absent. |

docs-devsite/firestore_pipelines.expression.md (81)

There's a capitalization inconsistency in the description. "Returns" should be in lowercase to be consistent with other descriptions in this file.

|  [coalesce(replacement, others)](./firestore_pipelines.expression.md#expressioncoalesce) |  | <b><i>(Public Preview)</i></b> Creates an expression that returns the first non-null, non-absent argument, without evaluating the rest of the arguments. When all arguments are null or absent, returns the last argument. |

docs-devsite/firestore_pipelines.expression.md (1513)

There's a capitalization inconsistency in the description. "Returns" should be in lowercase to be consistent with standard documentation style.

Creates an expression that returns the first non-null, non-absent argument, without evaluating the rest of the arguments. When all arguments are null or absent, returns the last argument.

docs-devsite/firestore_pipelines.expression.md (2599)

There's a formatting error in the documentation. The backslash before [Expression] should be removed to correctly render the link.

A new [Expression] representing the ifNull operation.

docs-devsite/firestore_pipelines.expression.md (2633)

There's a formatting error in the documentation. The backslash before [Expression] should be removed to correctly render the link.

A new [Expression] representing the ifNull operation.

docs-devsite/firestore_pipelines.md (95)

There's a capitalization inconsistency in the description. "Returns" should be in lowercase to be consistent with other descriptions in this file.

|  [coalesce(expression, replacement, others)](./firestore_pipelines.md#coalesce_00859cb) | <b><i>(Public Preview)</i></b> Creates an expression that returns the first non-null, non-absent argument, without evaluating the rest of the arguments. When all arguments are null or absent, returns the last argument. |

docs-devsite/firestore_pipelines.md (174)

There's a capitalization inconsistency in the description. "Returns" should be in lowercase to be consistent with other descriptions in this file.

|  [coalesce(fieldName, replacement, others)](./firestore_pipelines.md#coalesce_249958e) | <b><i>(Public Preview)</i></b> Creates an expression that returns the first non-null, non-absent argument, without evaluating the rest of the arguments. When all arguments are null or absent, returns the last argument. |

docs-devsite/firestore_pipelines.md (290-291)

The description for ifNull is incomplete. It should mention that it also checks for absent values, not just null values, to be consistent with the implementation and other parts of the documentation.

|  [ifNull(ifExpr, elseExpr)](./firestore_pipelines.md#ifnull_0e6d161) | <b><i>(Public Preview)</i></b> Creates an expression that returns the <code>elseExpr</code> argument if <code>ifExpr</code> is null or absent, else return the result of the <code>ifExpr</code> argument evaluation. |
|  [ifNull(ifExpr, elseValue)](./firestore_pipelines.md#ifnull_c34e5ed) | <b><i>(Public Preview)</i></b> Creates an expression that returns the <code>elseValue</code> argument if <code>ifExpr</code> is null or absent, else return the result of the <code>ifExpr</code> argument evaluation. |

docs-devsite/firestore_pipelines.md (2643)

There's a capitalization inconsistency in the description. "Returns" should be in lowercase to be consistent with standard documentation style.

Creates an expression that returns the first non-null, non-absent argument, without evaluating the rest of the arguments. When all arguments are null or absent, returns the last argument.

docs-devsite/firestore_pipelines.md (9195)

The description for ifNull is incomplete. It should mention that it also checks for absent values, not just null values, to be consistent with the implementation.

Creates an expression that returns the `elseExpr` argument if `ifExpr` is null or absent, else return the result of the `ifExpr` argument evaluation.

docs-devsite/firestore_pipelines.md (9242)

The description for the ifExpr parameter is inconsistent. It should state that it checks for "null or absence" to be accurate.

|  ifExpr | [Expression](./firestore_pipelines.expression.md#expression_class) | The expression to check for null or absence. |

docs-devsite/firestore_pipelines.md (9249)

There's a formatting error in the documentation. The backslash before [Expression] should be removed to correctly render the link.

A new [Expression] representing the ifNull operation.

docs-devsite/firestore_pipelines.md (9387)

There's a formatting error in the documentation. The backslash before [ifFieldName] should be removed to correctly render the link.

|  elseValue | unknown | The value that will be returned if [ifFieldName] is null or absent. |

packages/firestore/src/lite-api/expressions.ts (3187)

There's a capitalization inconsistency in the JSDoc. "Returns" should be in lowercase to follow standard JSDoc conventions.

   * Creates an expression that returns the first non-null, non-absent argument, without evaluating

packages/firestore/src/lite-api/expressions.ts (10600-10601)

The JSDoc for ifNull is incomplete. It should mention that it also checks for absent values, not just null values, to be consistent with the implementation.

 * Creates an expression that returns the `elseExpr` argument if `ifExpr` is null or absent, else
 * return the result of the `ifExpr` argument evaluation.

packages/firestore/src/lite-api/expressions.ts (10618-10619)

The JSDoc for ifNull is incomplete. It should mention that it also checks for absent values, not just null values, to be consistent with the implementation.

 * Creates an expression that returns the `elseValue` argument if `ifExpr` is null or absent, else
 * return the result of the `ifExpr` argument evaluation.

packages/firestore/src/lite-api/expressions.ts (10676)

There's a capitalization inconsistency in the JSDoc. "Returns" should be in lowercase to follow standard JSDoc conventions.

 * Creates an expression that returns the first non-null, non-absent argument, without evaluating

packages/firestore/src/lite-api/expressions.ts (10699)

There's a capitalization inconsistency in the JSDoc. "Returns" should be in lowercase to follow standard JSDoc conventions.

 * Creates an expression that returns the first non-null, non-absent argument, without evaluating

[milaGGL]

/gemini review

[gemini-code-assist]

Code Review

This pull request introduces support for the ifNull and coalesce pipeline expressions in Firestore and Firestore Lite. The implementation includes adding these as static functions and instance methods on the Expression class, updating API review files, and providing comprehensive documentation and integration tests. The review feedback identifies minor documentation issues, such as rendering artifacts in markdown blockquotes and incomplete sentences that fail to properly contrast ifNull with ifAbsent.

[dlarocque]

Is CI failing because these are not yet in prod? https://github.com/firebase/firebase-js-sdk/actions/runs/23653752018/job/68906986246?pr=9753

[dlarocque]

LGTM after removing @beta tags.

[dlarocque]

After #9772 these beta tags will be removed. Can you remove them from this PR?

[yvonnep165]

LGTM pending the auto checks results.