How to Calculate LOC for BlockStmt

[Edisonwudi]

Description of the issue

I'm currently analyzing Java code to identify opportunities for refactoring switch statements. One crucial metric I need is the number of lines of code (LOC). However, I've run into a problem: the predicates getNumberOfLinesOfCode() and getNumberOfCommentLines() don't work for BlockStmt, as noted in #10199. Additionally, I've found that getEndLine() and getStartLine() return the same value for both SwitchStmt and BlockStmt. This makes it impossible to directly calculate the LOC for switch blocks. Is there a recommended way to calculate the LOC for BlockStmt?

Error Examples and Results

Example 1: Using getNumberOfLinesOfCode() on BlockStmt

from BlockStmt b
select b, b.getNumberOfLinesOfCode().toString() as loc

Result:
No results returned, even though BlockStmt clearly contains code.

Example 2: Using getEndLine() and getStartLine() on SwitchStmt

from SwitchStmt s
select s, s.getLocation().getStartLine() as start, s.getLocation().getEndLine() as end

Input Code:

void process(int x) {
  switch(x) {       // Line 2
    case 1: break;  // Line 3
    case 2: break;  // Line 4
  }                 // Line 5
}

Result:
start = 2, end = 2 (both values are the same, even though the switch block spans multiple lines).

[mbg]

Hi @Edisonwudi 👋🏻

Thanks for this report. That does look wrong to me. I will pass this on to the relevant engineering team.

[smowton]

Thanks for the report. I'll take a look at this as time permits; in the meantime, consider looking for child statements using the getAStmt() predicate -- for example, max([block, block.getAStmt()].getLocation().getEndLine())

[Edisonwudi]

Thank you very much for your prompt and helpful response! Your suggestion to use getAStmt() and recursively calculate the maximum end line number has completely resolved my issue. If the issue of BlockStmt not being able to correctly use getNumberOfLinesOfCode() and getEndLine() can be further resolved, I believe more developers will benefit from it.