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While most generated Golang types must have unique names by virtue of being based on their GraphQL type
counterpart,
which themselves must be unique, there are a few edge scenarios where conflicts can occur. This document describes
how those collisions are handled.
Enum Constants
Enum type generation is a prime example of where naming collisions can occur, as we build the const names per value as a composite of the Enum name and each individual value.
Example Problem
Currently, enum types are transposed as such:
# graphql
enum MyEnum {
value1
value2
value3
value4
}
Which will result in the following Golang:
// golang
type MyEnum string
const (
MyEnumValue1 MyEnum = "value1"
MyEnumValue2 MyEnum = "value2"
MyEnumValue3 MyEnum = "value3"
MyEnumValue4 MyEnum = "value4"
)
However, those above enum values are just strings. What if you encounter a scenario where the following is necessary:
# graphql
enum MyEnum {
value1
value2
value3
value4
Value4
Value_4
}
The Value4
and Value_4
enum values cannot be directly transposed into the same “pretty” naming convention as their
resulting constant names would conflict with the name for value4
, as so:
// golang
type MyEnum string
const (
MyEnumValue1 MyEnum = "value1"
MyEnumValue2 MyEnum = "value2"
MyEnumValue3 MyEnum = "value3"
MyEnumValue4 MyEnum = "value4"
MyEnumValue4 MyEnum = "Value4"
MyEnumValue4 MyEnum = "Value_4"
)
Which immediately leads to compilation errors as we now have three constants with the same name, but different values.
Resolution
- Store each name generated as part of a run for later comparison
- Try to coerce name into
CapitalCase
. Use if no conflicts.- This process attempts to break apart identifiers into “words”, identified by separating on capital letters, underscores, hyphens, and spaces.
- Each “word” is capitalized and appended to previous word.
- If non-composite name, append integer to end of name, starting at 0 and going to
math.MaxInt
- If composite name, in reverse order, the pieces of the name have a less opinionated converter applied
- If all else fails, append integer to end of name, starting at 0 and going to
math.MaxInt
The first step to produce a name that does not conflict with an existing name succeeds.
Examples
Example A
GraphQL:
# graphql
enum MyEnum {
Value
value
TitleValue
title_value
}
Go:
// golang
type MyEnum string
const (
MyEnumValue MyEnum = "Value"
MyEnumvalue MyEnum = "value"
MyEnumTitleValue MyEnum = "TitleValue"
MyEnumtitle_value MyEnum = "title_value"
)
Example B
GraphQL:
# graphql
enum MyEnum {
TitleValue
title_value
title_Value
Title_Value
}
Go:
// golang
type MyEnum string
const (
MyEnumTitleValue MyEnum = "TitleValue"
MyEnumtitle_value MyEnum = "title_value"
MyEnumtitle_Value MyEnum = "title_Value"
MyEnumTitle_Value MyEnum = "Title_Value"
)
Example C
GraphQL:
# graphql
enum MyEnum {
value
Value
}
Go:
// golang
type MyEnum string
const (
MyEnumValue = "value"
MyEnumValue0 = "Value"
)
Warning
Name collision resolution is handled per-name, as they come in. If you change the order of an enum, you could very well end up with the same constant resolving to a different value.
Lets mutate Example C:
Example C - State A
GraphQL:
# graphql
enum MyEnum {
value
Value
}
Go:
// golang
type MyEnum string
const (
MyEnumValue = "value"
MyEnumValue0 = "Value"
)
Example C - State B
GraphQL:
# graphql
enum MyEnum {
Value
value
}
Go:
// golang
type MyEnum string
const (
MyEnumValue = "Value"
MyEnumValue0 = "value"
)
Notice how the constant names are the same, but the value that each applies to has changed.