Nested conditional statements in map() lambda function fail

[Adunaphel]

Bicep version
Bicep CLI version 0.11.1 (030248d)

Describe the bug
A nested conditional statement inside a map() lambda function fails.

When deploying the following template:

var testArray = [
  {
    property1: 'test'
    property2: 1
  }
  {
    property1: 'dev'
    property2: 2
  }
  {
    property1: 'test'
    property2: 0
  }
  {
    property1: 'prod'
    property2: 1
  }
  {
    property1: 'prod'
    property2: 0
  }
  {
    property1: 'dev'
    property2: 0
  }
  {
    property1: 'test'
    property2: 0
  }
]

output testMap array = map(testArray, record => {
  result: record.property2 > 0 ? record.property1 : record.property1 =~ 'test' ? 'test!' : 'notTest!'
})

output testFor array = [for record in testArray: {
  result: record.property2 > 0 ? record.property1 : record.property1 =~ 'test' ? 'test!' : 'notTest!'
}]

The two outputs are expected to be the same, but the outputs are as follows:

Name             Type                       Value     
===============  =========================  ==========
testMap          Array                      [{"result":"test"},{"result":"dev"},{"result":""},{"result":""},{"result":""},{"result":""},{"result":""}]
testFor          Array                      [{"result":"test"},{"result":"dev"},{"result":"test!"},{"result":"prod"},{"result":"notTest!"},{"result":"notTest!"},{"result":"test!"}]

Clearly the nested conditional statement fails as soon as the false-value is processed.

To Reproduce
Steps to reproduce the behavior: deploy the above template.

[slavizh]

+1

[anthony-c-martin]

I believe this is the same issue as #8798 & #8843.

I dug into this, and found that the DeploymentEngine has an optimization to cache partial function values when using any of the or(), and() and if() ARM JSON functions (equivalent to &&, || and ternary (? :) in Bicep.

Unfortunately this is going to require a runtime fix. I have submitted this fix, which will be rolled out in the next ARM release (starting this week).

For now, the only thing I can recommend is avoiding using any of &&, || or : ? inside a lambda. Sorry that I can't offer anything more helpful at this time.

[jurjenoskam]

I am able to use if() ARM JSON in a lambda, but only when the conditional does not contain a lambda variable. Is that the same problem this issue is tracking?

In other words, this works as expected:

output output1 array = map(
  items(testObject),
  subObject => 1 == 2 ? [ 'yes' ] : [ 'no' ]
)

"output1": {
    "type": "Array",
    "value": [
      [
        "no"
      ],
      [
        "no"
      ]
    ]
  }

... but this doesn't (when the condition is false the ? : operator returns "" instead of the expected [ 'no ']):

output output2 array = map(
  items(testObject),
  subObject => subObject.key == 'a' ? [ 'yes' ] : [ 'no' ]
)

  "output2": {
    "type": "Array",
    "value": [
      [
        "yes"
      ],
      ""
    ]
  }

[anthony-c-martin]

@jurjenoskam - just confirmed it's the same issue. I've added a test case to verify this with #9102

[miqm]

@anthony-c-martin - any ETA on the release? just hit it with map + contains + ternary.

[jikuja]

@anthony-c-martin - any ETA on the release? just hit it with map + contains + ternary.

Example for this:
main.bicep:

targetScope = 'subscription'

module test 'inner.bicep' = {
  name: 'test'
}

// fails
/*
{
  "code": "DeploymentOutputEvaluationFailed",
  "message": "Unable to evaluate template outputs: 'mapped1,mapped2'. Please see error details and deployment operations. Please see https://aka.ms/arm-debug for usage details.",
  "details": [
    {
      "code": "DeploymentOutputEvaluationFailed",
      "target": "mapped1",
      "message": "The template output 'mapped1' is not valid: The language expression property 'one' doesn't exist, available properties are 'two'.."
    },
    {
      "code": "DeploymentOutputEvaluationFailed",
      "target": "mapped2",
      "message": "The template output 'mapped2' is not valid: The language expression property 'two' doesn't exist, available properties are 'one'.."
    }
  ]
}
*/
//var mapped1 = map(test.outputs.foo, arg => arg.one)
//var mapped2 = map(test.outputs.foo, arg => arg.two)


var mapped1 = map(test.outputs.foo, arg => contains(arg, 'one') ? arg.one : 'placeholder1' )

var mapped2 = map(test.outputs.foo, arg => contains(arg, 'two') ? arg.two : 'placeholder2' )
var mapped2a = map(test.outputs.foo, arg => {
  xx: contains(arg, 'two') ? arg.two : 'placeholder2' 
})


output mapped1 array = mapped1
output mapped2 array = mapped2
output mapped2a array = mapped2a

inner.bicep:

targetScope = 'subscription'

output foo array = [
  {
    one: 'one'
  }
  {
    two: 'two'
  }
  {
    three: 'three'
  }
  {
    four: 'four'
  }
]

Results:

"outputs": {
      "mapped1": {
        "type": "Array",
        "value": [
          "one",
          "",
          "",
          ""
        ]
      },
      "mapped2": {
        "type": "Array",
        "value": [
          "placeholder2",
          "",
          "",
          ""
        ]
      },
      "mapped2a": {
        "type": "Array",
        "value": [
          {
            "xx": "placeholder2"
          },
          {
            "xx": ""
          },
          {
            "xx": ""
          },
          {
            "xx": ""
          }
        ]
      }

[anthony-c-martin]

This has now been fixed and rolled out globally. Please open a new issue if you are still seeing this (or similar) behavior.