Update config validation logic for entities

[aaronburtle]

Why make this change?

Closes #3267

What is this change?

Alters the validation logic in the following way.

Is top-level config with data-source-files? (we call this a Root config file)
├── YES
│ ├── Has datasource? → ValidateEntityPresence (same rules as non-root)
│ ├── No datasource but has entities/autoentities? → ERROR
│ └── No datasource, no entities → VALID (children provide everything)
│ └── For each child → ValidateNonRootConfig(child, filename)
│
└── NO (standalone or child config)
├── No datasource? → ERROR: "data source is required"
└── Has datasource → ValidateEntityPresence

Note: A top-level config file without any children data-source files is NOT considered a root. And an intermediary config file, ie: is a child, that also has child configs is NOT a root. Only a top-level config with children configs is a Root.

ValidateEntityPresence

Count resolved autoentities from AutoentityResolutionCounts
total = manual entities + resolved autoentities

total == 0? → ERROR: "No entities found"
total > 0 but autoentities discovered nothing? → WARN: "Autoentities configured but none discovered"

No double messaging. If total is 0, only the error is recorded, not the warning.

How was this tested?

Truth table — top-level config

Variables (1 = present / non-empty, 0 = absent / empty):

• DSF — data-source-files present
• DS — data-source present
• E — manual entities count > 0
• AE — autoentities count > 0 (presence, not resolved count)

Path is determined by IsRootConfig = (DSF == 1) && !IsChildConfig.

#	DSF	DS	E	AE	AE resolved	Path	Expected	Test
1	0	0	0	0	—	Non-root	Error: "data source is required"	TestNonRootWithNoDataSourceProducesError
2	0	0	0	1	—	Non-root	Error: "data source is required"	covered by #1 — DS check fires first
3	0	0	1	0	—	Non-root	Error: "data source is required"	covered by #1
4	0	0	1	1	—	Non-root	Error: "data source is required"	covered by #1
5	0	1	0	0	—	Non-root	Error: "No entities found"	TestNonRootWithDataSourceAndNoEntitiesProducesError
6a	0	1	0	1	0	Non-root	Error: "No entities found"	TestNonRootWithDataSourceAndAutoentitiesResolvingZeroProducesError
6b	0	1	0	1	>0	Non-root	Valid	TestNonRootWithDataSourceAndAutoentitiesResolvingEntitiesIsValid
7	0	1	1	0	—	Non-root	Valid	TestNonRootWithDataSourceAndEntitiesIsValid
8a	0	1	1	1	0	Non-root	Valid + Warn	TestNonRootWithEntitiesAndAutoentitiesResolvingZeroLogsWarning
8b	0	1	1	1	>0	Non-root	Valid	covered by #7 / #6b combined
9	1	0	0	0	—	Root	Valid (children carry the load)	TestRootWithNoDataSourceAndNoEntitiesIsValid, TestRootConfigWithNoDataSourceAndNoEntitiesParses
10	1	0	0	1	—	Root	Error: "must not define entities or autoentities"	TestRootWithNoDataSourceButAutoentitiesProducesError
11	1	0	1	0	—	Root	Error: "must not define entities"	TestRootWithNoDataSourceButEntitiesProducesError
12	1	0	1	1	—	Root	Error	covered by #11
13	1	1	0	0	—	Root (with own DS)	Error: "No entities found"	TestRootWithDataSourceAndNoEntitiesProducesError
14a	1	1	0	1	0	Root (with own DS)	Error: "No entities found"	TestRootWithDataSourceAndAutoentitiesResolvingZeroProducesError
14b	1	1	0	1	>0	Root (with own DS)	Valid	TestRootWithDataSourceAndAutoentitiesResolvingEntitiesIsValid
15	1	1	1	0	—	Root (with own DS)	Valid	TestRootWithDataSourceAndEntitiesIsValid
16a	1	1	1	1	0	Root (with own DS)	Valid + Warn	TestRootWithEntitiesAndAutoentitiesResolvingZeroLogsWarning
16b	1	1	1	1	>0	Root (with own DS)	Valid	covered by #15 / #14b combined

Truth table — child config (validated when iterating root.ChildConfigs)

Children are always treated as non-root regardless of their own data-source-files.

#	DS	E	AE	AE resolved	Expected	Test
C1	0	0	0	—	Error naming the child file: "data source is required"	TestChildWithNoDataSourceProducesNamedError
C2	0	*	*	—	Error naming the child file: "data source is required"	covered by C1
C3	1	0	0	—	Error naming the child file: "No entities found"	TestChildWithDataSourceAndNoEntitiesProducesNamedError
C4a	1	0	1	0	Error naming the child file: "No entities found"	TestChildWithDataSourceAndAutoentitiesResolvingZeroProducesNamedError
C4b	1	0	1	>0	Valid	covered by C5 (resolved entities behave the same as manual entities)
C5	1	1	0	—	Valid	implicitly via TestRootWithDataSourceAndEntitiesIsValid setup
C6a	1	1	1	0	Valid + Warn naming the child file	TestChildWithEntitiesAndAutoentitiesResolvingZeroLogsNamedWarning
C6b	1	1	1	>0	Valid	covered by C5

Other scenarios

Scenario	Expected	Test
Connection-string error gates entity validation (no entity error fires when DB unreachable)	IsConfigValid == false due to connection error only	TestValidateNonRootZeroEntitiesWithInvalidConnectionString
Config with no entities parses cleanly (constructor no longer throws) and IsConfigValid returns false without throwing	parse OK, validate fails	TestValidateConfigWithNoEntitiesProducesCleanError (modified)
Root parses successfully without a data source	parse OK, IsRootConfig == true	TestRootConfigWithNoDataSourceAndNoEntitiesParses
Non-root with DS and no entities parses successfully	parse OK, IsRootConfig == false	TestNonRootConfigWithDataSourceAndNoEntitiesParses
Autoentities present but resolve to nothing — must not crash, must not double-message with "No entities found"	no crash; only "No entities found" if total = 0	ValidateAutoentitiesConfiguration (modified to isValidateOnly: true)

New tests:

TestRootConfigWithNoDataSourceAndNoEntitiesParses Root config (has data-source-files) without datasource parses OK
TestNonRootConfigWithDataSourceAndNoEntitiesParses Non-root config with datasource + no entities parses OK (validation catches it later)
TestNonRootWithDataSourceAndNoEntitiesProducesError Calls ValidateDataSourceAndEntityPresence directly, error recorded
TestNonRootWithNoDataSourceProducesError No datasource, error with "data source is required"
TestNonRootWithDataSourceAndEntitiesIsValid Datasource + entities, no errors
TestRootWithNoDataSourceAndNoEntitiesIsValid Root with child, no own datasource, valid
TestRootWithNoDataSourceButEntitiesProducesError Root with entities but no datasource, error
TestRootWithDataSourceAndEntitiesIsValid Root with own datasource + entities, valid
TestChildWithDataSourceAndNoEntitiesProducesNamedError Child with no entities, error names the child file
TestChildWithNoDataSourceProducesNamedError Child with no datasource, error names the child file
TestNonRootWithDataSourceAndAutoentitiesResolvingZeroProducesError Non-root with only autoentities that resolve to 0
TestNonRootWithDataSourceAndAutoentitiesResolvingEntitiesIsValid Non-root with only autoentities resolving > 0 entities
TestNonRootWithEntitiesAndAutoentitiesResolvingZeroLogsWarning Non-root with manual entities + autoentities resolving 0
TestRootWithNoDataSourceButAutoentitiesProducesError Root with no datasource but autoentities defined
TestRootWithDataSourceAndNoEntitiesProducesError Root with own datasource and zero entities/autoentities
TestRootWithDataSourceAndAutoentitiesResolvingZeroProducesError Root with own datasource and autoentities resolving 0
TestRootWithDataSourceAndAutoentitiesResolvingEntitiesIsValid Root with own datasource and autoentities resolving > 0
TestRootWithEntitiesAndAutoentitiesResolvingZeroLogsWarning Root with own datasource, manual entities, and autoentities resolving 0
TestChildWithDataSourceAndAutoentitiesResolvingZeroProducesNamedError Child with autoentities-only resolving 0
TestChildWithEntitiesAndAutoentitiesResolvingZeroLogsNamedWarning Child with manual entities + autoentities resolving 0

Modified tests:

TestValidateConfigWithNoEntitiesProducesCleanError Replaced main's version (expected parse failure) with ours: parse succeeds, IsConfigValid returns false
ValidateAutoentitiesConfiguration Changed to isValidateOnly: true, asserts no crashes instead of zero errors

[Copilot]

Pull request overview

Adds a CLI validation-time warning to help users detect “valid” configs that define no entities (and have no autoentities / multi-config datasource files), aligning dab validate behavior with Issue #3267.

Changes:

• Adds a WarnIfNoEntitiesDefined(RuntimeConfig) helper and invokes it during dab validate.
• Refactors IsConfigValid to log the new structural warning regardless of overall validation outcome.
• Adds a CLI unit test that verifies the warning is logged for a minimal config with zero entities.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
src/Cli/ConfigGenerator.cs	Introduces and invokes the new “zero entities” warning helper during dab validate.
src/Cli.Tests/ValidateConfigTests.cs	Adds a unit test verifying the warning is emitted for an empty-entities config.

[anushakolan]

/azp run

[Aniruddh25]

IsRestEnabled check needs to be fixed.

[Aniruddh25]

Some tests fail, and some renames necessary.