From 93a84684a5eefe0b9df54a69960742cf26dc8e66 Mon Sep 17 00:00:00 2001
From: Max Schaefer <max@semmle.com>
Date: Wed, 5 Feb 2020 13:42:06 +0000
Subject: [PATCH] Remove predicate `CallExpr.calls`.

This sort of reasoning should be done at the data-flow level.
---
 ql/src/semmle/go/Expr.qll | 17 ++++++-----------
 1 file changed, 6 insertions(+), 11 deletions(-)

diff --git a/ql/src/semmle/go/Expr.qll b/ql/src/semmle/go/Expr.qll
index 2fa9559809c..b86c73d3697 100644
--- a/ql/src/semmle/go/Expr.qll
+++ b/ql/src/semmle/go/Expr.qll
@@ -442,14 +442,6 @@ class CallExpr extends CallOrConversionExpr {
   /** Gets the expression representing the function being called. */
   Expr getCalleeExpr() { result = getChildExpr(0) }
 
-  /** Holds if this call is of the form `base.method(...)`. */
-  predicate calls(Expr base, string method) {
-    exists(SelectorExpr callee | callee = getCalleeExpr().stripParens() |
-      callee.getBase() = base and
-      method = callee.getSelector().getName()
-    )
-  }
-
   /** Gets the `i`th argument expression of this call (0-based). */
   Expr getArgument(int i) {
     i >= 0 and
@@ -462,10 +454,13 @@ class CallExpr extends CallOrConversionExpr {
   /** Gets the number of argument expressions of this call. */
   int getNumArgument() { result = count(getAnArgument()) }
 
-  /** Gets the name of the invoked function or method. */
+  /** Gets the name of the invoked function or method if it can be determined syntactically. */
   string getCalleeName() {
-    result = getCalleeExpr().stripParens().(Ident).getName() or
-    calls(_, result)
+    exists(Expr callee | callee = getCalleeExpr().stripParens() |
+      result = callee.(Ident).getName()
+      or
+      result = callee.(SelectorExpr).getSelector().getName()
+    )
   }
 
   /** Gets the declared target of this call. */