Multiple matches generate unexpected cypher

[aekobear]

When using the Query object to create a query with multiple match statements, the statements are merged into a single match. The resulting cypher produces different results than it would have, had all the matches been preserved.

Given that there are situations where multiple matches are explicitly desired, and given that there is already a notation for writing a multi-pattern match:

q.match('pattern a', 'pattern b')

I think it is most intuitive to have multiple matches retained when the query is converted to cypher.

Additional information which could be helpful if relevent to your issue:

Code example (inline, gist, or repo)

For example, take a graph of a Repo named Test and a chain of dependencies named D1, D2 and D3:

The query:

q.match('(r:Repo { name: "Test" })-[*]-(d)')
  .match('(d)-[e]-()')
  .return(:d, :e)

generates the cypher:

MATCH (r:Repo { name: "Test" })-[*]-(d), (d)-[e]-() RETURN d, e

which returns only the dependencies D1 and D2.

Forcing multiple matches with a break:

q.match('(r:Repo { name: "Test" })-[*]-(d)')
  .break
  .match('(d)-[e]-()')
  .return(:d, :e)

generates the cypher:

MATCH (r:Repo { name: "Test" })-[*]-(d) MATCH (d)-[e]-() RETURN d, e

which returns all dependencies D1, D2 and D3.

Runtime information:

Neo4j database version: 3.5.0 neo4j gem version: N/A neo4j-core gem version: 9.0.0

[jorroll]

Related to #255