StringIndexOutOfBounds exceptions with relative server urls when loading from a file path that includes spaces

Getting this error when parsing a file: java.lang.StringIndexOutOfBoundsException: begin 0, end -1, length 25

at java.base/java.lang.String.checkBoundsBeginEnd(String.java:3319)
at java.base/java.lang.String.substring(String.java:1874)
at io.swagger.v3.parser.util.OpenAPIDeserializer.getServer(OpenAPIDeserializer.java:481)
at io.swagger.v3.parser.util.OpenAPIDeserializer.getServersList(OpenAPIDeserializer.java:435)
at io.swagger.v3.parser.util.OpenAPIDeserializer.parseRoot(OpenAPIDeserializer.java:192)
at io.swagger.v3.parser.util.OpenAPIDeserializer.deserialize(OpenAPIDeserializer.java:149)
at io.swagger.v3.parser.OpenAPIV3Parser.parseJsonNode(OpenAPIV3Parser.java:134)
at io.swagger.v3.parser.OpenAPIV3Parser.readContents(OpenAPIV3Parser.java:152)
at io.swagger.v3.parser.OpenAPIV3Parser.readLocation(OpenAPIV3Parser.java:89)
at io.swagger.parser.OpenAPIParser.readLocation(OpenAPIParser.java:16)

after debugging I noticed that the parser is failing to read

servers:
  - url: /just/an/example

but when removing the dash before the url, the parsing goes fine, so he servers part becomes:

servers:
   url: /just/an/example

[HrFlorianHoffmann]

We worked around this issue with the following piece of code:

servers:
  - url: '{host}/my/path/v1'
    variables:
      host:
        default: ''

The empty dummy variable avoids that the statements value.indexOf("{") and value.indexOf("}") fail.

[HrFlorianHoffmann]

Tried to produce a pull request that provides a failing unit test for this issue, but failed.

I looked up the class OpenAPIDeserializerTest and added another unit test that supplies our exact yaml specification as a string to the OpenAPIV3Parser.readContents method. However, we didn’t get the expected exception.

I assume that the unit tests call the parser differently than the Maven plug-in. More precisely, I assume that the plugin calls the parser with a file location, such that the input parameter path of the method getServer is filled with a value. In the unit tests, this parameter is null, such that the entry condition path != null skips the affected code.

I tried to force the unit test to supply path with a value, by making the private method readContents in OpenAPIV3Parser public and calling it directly, but this didn’t work out, as the location/path variable has lots of other effects, and the code aborted with an unrelated other exception.

Setting up a reproducible sample needs more know-how about the parser’s details than I currently have.