Add string-valued variables to exvar.
R=r
APPROVED=r
DELTA=62 (58 added, 1 deleted, 3 changed)
OCL=27756
CL=27877
diff --git a/src/lib/exvar.go b/src/lib/exvar.go
index d96e40a..a5d91f3 100644
--- a/src/lib/exvar.go
+++ b/src/lib/exvar.go
@@ -19,6 +19,7 @@
reservedPrefix = "x-";
mismatchedInt = reservedPrefix + "mismatched-int";
mismatchedMap = reservedPrefix + "mismatched-map";
+ mismatchedStr = reservedPrefix + "mismatched-str";
)
// exVar is an abstract type for all exported variables.
@@ -44,8 +45,14 @@
return s
}
+// strVar is a string variable, and satisfies the exVar interface.
+type strVar string;
+
+func (s strVar) String() string {
+ return fmt.Sprintf("%q", s)
+}
+
// TODO(dsymonds):
-// - string-valued vars
// - dynamic lookup vars (via chan?)
type exVars struct {
@@ -119,6 +126,22 @@
return &m
}
+// getOrInitStrVar either gets or initializes a strVar called name.
+func (state *exVars) getOrInitStrVar(name string) *strVar {
+ if v, ok := state.vars[name]; ok {
+ // Existing var
+ if mv, ok := v.(*strVar); ok {
+ return mv
+ }
+ // Type mismatch.
+ return state.getOrInitStrVar(mismatchedStr)
+ }
+ // New var
+ sv := new(strVar);
+ state.vars[name] = sv;
+ return sv
+}
+
// IncrementInt adds inc to the integer-valued var called name.
func IncrementInt(name string, inc int) {
workSync(func(state *exVars) {
@@ -152,6 +175,13 @@
})
}
+// SetStr sets the string-valued var called name to value.
+func SetStr(name string, value string) {
+ workSync(func(state *exVars) {
+ *state.getOrInitStrVar(name) = value
+ })
+}
+
// GetInt retrieves an integer-valued var called name.
func GetInt(name string) int {
var i int;
@@ -171,6 +201,15 @@
return i
}
+// GetStr retrieves a string-valued var called name.
+func GetStr(name string) string {
+ var s string;
+ workSync(func(state *exVars) {
+ s = *state.getOrInitStrVar(name)
+ });
+ return s
+}
+
// String produces a string of all the vars in textual format.
func String() string {
s := "";
diff --git a/src/lib/exvar_test.go b/src/lib/exvar_test.go
index 8e9b123..89a470a 100644
--- a/src/lib/exvar_test.go
+++ b/src/lib/exvar_test.go
@@ -14,14 +14,14 @@
// Unknown exvar should be zero.
x := GetInt("requests");
if x != 0 {
- t.Errorf("Get(nonexistent) = %v, want 0", x)
+ t.Errorf("GetInt(nonexistent) = %v, want 0", x)
}
IncrementInt("requests", 1);
IncrementInt("requests", 3);
x = GetInt("requests");
if x != 4 {
- t.Errorf("Get('requests') = %v, want 4", x)
+ t.Errorf("GetInt('requests') = %v, want 4", x)
}
out := String();
@@ -31,10 +31,23 @@
}
}
+func TestStringVar(t *testing.T) {
+ // Unknown exvar should be empty string.
+ if s := GetStr("name"); s != "" {
+ t.Errorf("GetStr(nonexistent) = %q, want ''", s)
+ }
+
+ SetStr("name", "Mike");
+ if s := GetStr("name"); s != "Mike" {
+ t.Errorf("GetStr('name') = %q, want 'Mike'", s)
+ }
+}
+
func TestMismatchedCounters(t *testing.T) {
// Make sure some vars exist.
GetInt("requests");
GetMapInt("colours", "red");
+ GetStr("name");
IncrementInt("colours", 1);
if x := GetInt("x-mismatched-int"); x != 1 {
@@ -43,7 +56,12 @@
IncrementMapInt("requests", "orange", 1);
if x := GetMapInt("x-mismatched-map", "orange"); x != 1 {
- t.Errorf("GetMapInt('x-mismatched-int', 'orange') = %v, want 1", x)
+ t.Errorf("GetMapInt('x-mismatched-map', 'orange') = %v, want 1", x)
+ }
+
+ SetStr("requests", "apple");
+ if s := GetStr("x-mismatched-str"); s != "apple" {
+ t.Errorf("GetStr('x-mismatched-str') = %q, want 'apple'", s)
}
}
