isSanitizerGuard works incorrectly when the function name startwith "isValid"

i am try the the codeql query from https://codeql.github.com/docs/codeql-language-guides/analyzing-data-flow-in-javascript-and-typescript/ ;
the code to analysis is copied from tutorial
```
const fs = require('fs'),
path = require('path');

function readFileHelper(p) { // #2
if (!checkPath(p)){
return;
}
fs.readFile(p, // #4
'utf8', (err, data) => {
if (err) throw err;
console.log(data);
});
}

readFileHelper(process.argv[2]); // #1
```
and the query is also from tutorial
```
/**
* @name Find usage of request.body and request.query in Express.js
* @description Finds variables assigned from request.body and request.query in Express.js applications.
* @kind problem
* @id js/express-request-body-query
*/
import javascript

class CheckPathSanitizerGuard extends TaintTracking::SanitizerGuardNode, DataFlow::CallNode {
CheckPathSanitizerGuard() { this.getCalleeName() = "checkPath" }

override predicate sanitizes(boolean outcome, Expr e) {
outcome = true and
e = getArgument(0).asExpr()
}
}

class CommandLineFileNameConfiguration extends TaintTracking::Configuration {
CommandLineFileNameConfiguration() { this = "CommandLineFileNameConfiguration" }

override predicate isSource(DataFlow::Node source) {
DataFlow::globalVarRef("process").getAPropertyRead("argv").getAPropertyRead() = source
}

override predicate isSink(DataFlow::Node sink) {
DataFlow::moduleMember("fs", "readFile").getACall().getArgument(0) = sink
}
override predicate isSanitizerGuard(TaintTracking::SanitizerGuardNode nd) {
nd instanceof CheckPathSanitizerGuard
}
}

from CommandLineFileNameConfiguration cfg, DataFlow::Node source, DataFlow::Node sink
where cfg.hasFlow(source, sink)
select source, "12312323"
```
i use command line cli (2.18.3 newest version) to get the result
```
codeql database create codeqldb --language=javascript
codeql database analyze --rerun --threads 0 /test2.ql --format=sarif-latest --output=1.sarif
```
It all works fine.
Then i change the ql, this line
```
override predicate sanitizes(boolean outcome, Expr e) {
outcome = true and
e = getArgument(0).asExpr()
}
```
to
```
override predicate sanitizes(boolean outcome, Expr e) {
outcome = false and
e = getArgument(0).asExpr()
}
```
As expected, it does not sanitize the output.
The wierd thing is, if i change the function name of "checkPath", to "isValid", the sanitizer works very wierd, it sanitize the output no matter outcome is true of false. code is like:
```
const fs = require('fs'),
path = require('path');

function readFileHelper(p) { // #2
if (!isValid(p)){
return;
}
fs.readFile(p, // #4
'utf8', (err, data) => {
if (err) throw err;
console.log(data);
});
}

readFileHelper(process.argv[2]); // #1
```
ql is like
```
/**
* @name Find usage of request.body and request.query in Express.js
* @description Finds variables assigned from request.body and request.query in Express.js applications.
* @kind problem
* @id js/express-request-body-query
*/
import javascript

class CheckPathSanitizerGuard extends TaintTracking::SanitizerGuardNode, DataFlow::CallNode {
CheckPathSanitizerGuard() { this.getCalleeName() = "isValid" }

override predicate sanitizes(boolean outcome, Expr e) {
outcome = false and
e = getArgument(0).asExpr()
}
}

class CommandLineFileNameConfiguration extends TaintTracking::Configuration {
CommandLineFileNameConfiguration() { this = "CommandLineFileNameConfiguration" }

override predicate isSource(DataFlow::Node source) {
DataFlow::globalVarRef("process").getAPropertyRead("argv").getAPropertyRead() = source
}

override predicate isSink(DataFlow::Node sink) {
DataFlow::moduleMember("fs", "readFile").getACall().getArgument(0) = sink
}
override predicate isSanitizerGuard(TaintTracking::SanitizerGuardNode nd) {
nd instanceof CheckPathSanitizerGuard
}
}

from CommandLineFileNameConfiguration cfg, DataFlow::Node source, DataFlow::Node sink
where cfg.hasFlow(source, sink)
select source, "12312323"
```

The only thing changed is the function name. "isValid" is not some special thing in js i think. I try other function names, everything start with isValid works abnormal, like "isValidd" "isValidg", anything else works correctly, like "isVali"