-- in.cue --
a: {
	foo: a: 1
	[X = =~"foo"]: {
		b:    1
		name: X
	}
}
d: a & {
	"foobar": {
		c: 2
	}
}

t1: {
	#a: {
		[>"e" & <"z"]: int
	}
	b: #a & {f: 4}
	c: #a & {z: 4}
}

t2: {
	#a: {
		["x" | "y"]: int
	}
	b: #a & {x: 4}
	c: #a & {z: 4}
}

-- issue2109.cue --
// Detect cycle:
// The pattern constraint of FlagsURLS is applied to countries (because
// FlagsURLs  is embedded. But the pattern constraint itself refers to
// countries. So countries -> or(countries) -> countries.
//
// Theoretically, or(countries) can be resolved without a cycle. And then we
// could see it does not apply to countries. For now we stick with this
// approach understanding that it is easier to relax later.
patternCycle: issue2109: p1: {
	countries: ["US", "GB", "AU"]
	FlagsURLs: {[or(countries)]: string}
	FlagsURLs
}
patternCycle: issue2109: p2: {
	FlagsURLs: {[or(countries)]: string}
	FlagsURLs
	countries: ["US", "GB", "AU"]
}
patternCycle: issue2109: p3: {
	FlagsURLs
	FlagsURLs: {[or(countries)]: string}
	countries: ["US", "GB", "AU"]
}

patternCycle: t1: p1: {
	countries: "US" | "GB" | "AU"
	FlagsURLs: {[countries]: string}
	FlagsURLs
}
patternCycle: t1: p2: {
	FlagsURLs
	countries: "US" | "GB" | "AU"
	FlagsURLs: {[countries]: string}
}
patternCycle: t1: p3: {
	FlagsURLs
	FlagsURLs: {[countries]: string}
	countries: "US" | "GB" | "AU"
}

-- out/eval/stats --
Leaks:  4
Freed:  80
Reused: 73
Allocs: 11
Retain: 12

Unifications: 63
Conjuncts:    126
Disjuncts:    90
-- out/eval --
Errors:
t1.c.z: field not allowed:
    ./in.cue:15:6
    ./in.cue:19:5
    ./in.cue:19:11
t2.c.z: field not allowed:
    ./in.cue:23:6
    ./in.cue:27:5
    ./in.cue:27:11
patternCycle.issue2109.p1.countries: cyclic pattern constraint:
    ./issue2109.cue:11:15
    ./issue2109.cue:10:13
patternCycle.issue2109.p2.countries: cyclic pattern constraint:
    ./issue2109.cue:15:15
    ./issue2109.cue:17:13
patternCycle.issue2109.p3.countries: cyclic pattern constraint:
    ./issue2109.cue:21:15
    ./issue2109.cue:22:13
patternCycle.t1.p1.countries: cyclic pattern constraint:
    ./issue2109.cue:27:15
    ./issue2109.cue:26:13
patternCycle.t1.p2.countries: cyclic pattern constraint:
    ./issue2109.cue:33:15
    ./issue2109.cue:32:13
patternCycle.t1.p3.countries: cyclic pattern constraint:
    ./issue2109.cue:37:15
    ./issue2109.cue:38:13

Result:
(_|_){
  // [eval]
  a: (struct){
    foo: (struct){
      a: (int){ 1 }
      b: (int){ 1 }
      name: (string){ "foo" }
    }
  }
  d: (struct){
    foo: (struct){
      a: (int){ 1 }
      b: (int){ 1 }
      name: (string){ "foo" }
    }
    foobar: (struct){
      c: (int){ 2 }
      b: (int){ 1 }
      name: (string){ "foobar" }
    }
  }
  t1: (_|_){
    // [eval]
    #a: (#struct){
    }
    b: (#struct){
      f: (int){ 4 }
    }
    c: (_|_){
      // [eval]
      z: (_|_){
        // [eval] t1.c.z: field not allowed:
        //     ./in.cue:15:6
        //     ./in.cue:19:5
        //     ./in.cue:19:11
      }
    }
  }
  t2: (_|_){
    // [eval]
    #a: (#struct){
    }
    b: (#struct){
      x: (int){ 4 }
    }
    c: (_|_){
      // [eval]
      z: (_|_){
        // [eval] t2.c.z: field not allowed:
        //     ./in.cue:23:6
        //     ./in.cue:27:5
        //     ./in.cue:27:11
      }
    }
  }
  patternCycle: (_|_){
    // [eval]
    issue2109: (_|_){
      // [eval]
      p1: (_|_){
        // [eval]
        countries: (_|_){
          // [eval] patternCycle.issue2109.p1.countries: cyclic pattern constraint:
          //     ./issue2109.cue:11:15
          //     ./issue2109.cue:10:13
          0: (string){ "US" }
          1: (string){ "GB" }
          2: (string){ "AU" }
        }
        FlagsURLs: (struct){
        }
      }
      p2: (_|_){
        // [eval]
        FlagsURLs: (struct){
        }
        countries: (_|_){
          // [eval] patternCycle.issue2109.p2.countries: cyclic pattern constraint:
          //     ./issue2109.cue:15:15
          //     ./issue2109.cue:17:13
          0: (_|_){// "US"
          }
          1: (_|_){// "GB"
          }
          2: (_|_){// "AU"
          }
        }
      }
      p3: (_|_){
        // [eval]
        FlagsURLs: (struct){
        }
        countries: (_|_){
          // [eval] patternCycle.issue2109.p3.countries: cyclic pattern constraint:
          //     ./issue2109.cue:21:15
          //     ./issue2109.cue:22:13
          0: (_|_){// "US"
          }
          1: (_|_){// "GB"
          }
          2: (_|_){// "AU"
          }
        }
      }
    }
    t1: (_|_){
      // [eval]
      p1: (_|_){
        // [eval]
        countries: (_|_){
          // [eval] patternCycle.t1.p1.countries: cyclic pattern constraint:
          //     ./issue2109.cue:27:15
          //     ./issue2109.cue:26:13
        }
        FlagsURLs: (struct){
        }
      }
      p2: (_|_){
        // [eval]
        countries: (_|_){
          // [eval] patternCycle.t1.p2.countries: cyclic pattern constraint:
          //     ./issue2109.cue:33:15
          //     ./issue2109.cue:32:13
        }
        FlagsURLs: (struct){
        }
      }
      p3: (_|_){
        // [eval]
        FlagsURLs: (struct){
        }
        countries: (_|_){
          // [eval] patternCycle.t1.p3.countries: cyclic pattern constraint:
          //     ./issue2109.cue:37:15
          //     ./issue2109.cue:38:13
        }
      }
    }
  }
}
-- out/compile --
--- in.cue
{
  a: {
    foo: {
      a: 1
    }
    [=~"foo"]: {
      b: 1
      name: 〈1;-〉
    }
  }
  d: (〈0;a〉 & {
    foobar: {
      c: 2
    }
  })
  t1: {
    #a: {
      [(>"e" & <"z")]: int
    }
    b: (〈0;#a〉 & {
      f: 4
    })
    c: (〈0;#a〉 & {
      z: 4
    })
  }
  t2: {
    #a: {
      [("x"|"y")]: int
    }
    b: (〈0;#a〉 & {
      x: 4
    })
    c: (〈0;#a〉 & {
      z: 4
    })
  }
}
--- issue2109.cue
{
  patternCycle: {
    issue2109: {
      p1: {
        countries: [
          "US",
          "GB",
          "AU",
        ]
        FlagsURLs: {
          [or(〈1;countries〉)]: string
        }
        〈0;FlagsURLs〉
      }
    }
  }
  patternCycle: {
    issue2109: {
      p2: {
        FlagsURLs: {
          [or(〈1;countries〉)]: string
        }
        〈0;FlagsURLs〉
        countries: [
          "US",
          "GB",
          "AU",
        ]
      }
    }
  }
  patternCycle: {
    issue2109: {
      p3: {
        〈0;FlagsURLs〉
        FlagsURLs: {
          [or(〈1;countries〉)]: string
        }
        countries: [
          "US",
          "GB",
          "AU",
        ]
      }
    }
  }
  patternCycle: {
    t1: {
      p1: {
        countries: ("US"|"GB"|"AU")
        FlagsURLs: {
          [〈1;countries〉]: string
        }
        〈0;FlagsURLs〉
      }
    }
  }
  patternCycle: {
    t1: {
      p2: {
        〈0;FlagsURLs〉
        countries: ("US"|"GB"|"AU")
        FlagsURLs: {
          [〈1;countries〉]: string
        }
      }
    }
  }
  patternCycle: {
    t1: {
      p3: {
        〈0;FlagsURLs〉
        FlagsURLs: {
          [〈1;countries〉]: string
        }
        countries: ("US"|"GB"|"AU")
      }
    }
  }
}