Tests for file models

Author: egregius313

go/ql/test/library-tests/semmle/go/dataflow/flowsources/local/file/test.expected

@@ -0,0 +1,3 @@
+| test.go:6:2:6:33 | ... := ...[0] |
+| test.go:15:2:15:51 | ... := ...[0] |
+| test.go:24:2:24:37 | ... := ...[0] |

go/ql/test/library-tests/semmle/go/dataflow/flowsources/local/file/test.ext.yml

@@ -0,0 +1,6 @@
+extensions:
+  - addsTo:
+      pack: codeql/threat-models
+      extensible: threatModelConfiguration
+    data:
+      - ["file", true, 0]

go/ql/test/library-tests/semmle/go/dataflow/flowsources/local/file/test.go

@@ -0,0 +1,29 @@
+package test
+
+import "os"
+
+func open() {
+	file, err := os.Open("file.txt")
+	if err != nil {
+		return
+	}
+	defer file.Close()
+	file.Read([]byte{1, 2, 3})
+}
+
+func openFile() {
+	file, err := os.OpenFile("file.txt", os.O_RDWR, 0)
+	if err != nil {
+		return
+	}
+	defer file.Close()
+	file.Read([]byte{1, 2, 3})
+}
+
+func readFile() {
+	data, err := os.ReadFile("file.txt")
+	if err != nil {
+		return
+	}
+	_ = data
+}

go/ql/test/library-tests/semmle/go/dataflow/flowsources/local/file/test.ql

@@ -0,0 +1,5 @@
+import go
+
+from DataFlow::Node source
+where source instanceof ThreatModelFlowSource
+select source