add a test for resolving offsets

src/shellpop.zig

@@ -25,41 +25,38 @@ const ShellPopcon = struct {
     counts: std.StringHashMap(u32),
     allocator: Allocator,
     const Self = @This();
-    const KV = struct {
+    const KV = struct { shell: []const u8, score: u32 };
-        shell: []const u8,
-        score: u32,
-    };
 
     const ShellSections = struct {
         index: BoundedArray(ShellIndex, MaxShells),
         blob: BoundedArray(u8, MaxShells * MaxShellLen),
+        indices: StringHashMap(u10),
 
-        offsets: StringHashMap(u10),
+        // initializes and populates shell sections. All strings are copied,
-
+        // nothing is owned.
-        // initializes and populates shell sections. All strings are copied, nothing is owned.
+        pub fn init(
-        pub fn init(allocator: Allocator, shells: BoundedArray([]const u8, MaxShells)) !ShellSections {
+            allocator: Allocator,
+            shells: BoundedArray([]const u8, MaxShells),
+        ) !ShellSections {
             var self = ShellSections{
                 .index = try BoundedArray(ShellIndex, MaxShells).init(shells.len),
                 .blob = try BoundedArray(u8, MaxShells * MaxShellLen).init(0),
-                .offsets = StringHashMap(u10).init(allocator),
+                .indices = StringHashMap(u10).init(allocator),
             };
             var offset: u10 = 0;
             var idx: u10 = 0;
             while (idx < shells.len) {
-                //const stderr = std.io.getStdErr().writer();
-                //try stderr.print("\n", .{});
-
                 const len = @intCast(u6, shells.get(idx).len);
                 try self.blob.appendSlice(shells.get(idx));
                 const ourShell = self.blob.constSlice()[offset .. offset + len];
-                try self.offsets.put(ourShell, idx);
+                try self.indices.put(ourShell, idx);
                 self.index.set(idx, ShellIndex{
-                    .offset = offset >> 2, // all shells are padded by 4
+                    .offset = offset >> 2,
                     .len = len,
                 });
                 offset += len;
 
-                // if offset is not multiple by 4, make it so, and append the offset.
+                // Padd padding to make offset divisible by 4.
                 const padding = (offset + 3) & ~@intCast(u10, 3);
                 offset += padding;
                 try self.blob.appendNTimes(0, padding);
@@ -69,12 +66,12 @@ const ShellPopcon = struct {
         }
 
         pub fn deinit(self: *ShellSections) void {
-            self.offsets.deinit();
+            self.indices.deinit();
             self.* = undefined;
         }
 
-        pub fn getOffset(self: *ShellSections, shell: []const u8) ?u10 {
+        pub fn getIndex(self: *ShellSections, shell: []const u8) ?u10 {
-            return self.offsets.get(shell);
+            return self.indices.get(shell);
         }
     };
 
@@ -167,7 +164,21 @@ test "basic shellpopcon" {
     defer sections.deinit();
     try testing.expectEqual(sections.index.len, 3); // all but "nobody" qualify
 
-    try testing.expectEqual(sections.getOffset(long).?, 0);
+    // TODO(motiejus): reverse the arguments: first should be "expected".
-    try testing.expectEqual(sections.getOffset(zsh).?, 1);
+    try testing.expectEqual(sections.getIndex(long).?, 0);
-    try testing.expectEqual(sections.getOffset(bash).?, 2);
+    try testing.expectEqual(sections.getIndex(zsh).?, 1);
+    try testing.expectEqual(sections.getIndex(bash).?, 2);
+    try testing.expectEqual(sections.getIndex(nobody), null);
+
+    const longIndex = sections.getIndex(long).?;
+    const start = sections.index.get(longIndex).offset << 2;
+    const end = start + sections.index.get(longIndex).len;
+    const gotLong = sections.blob.constSlice()[start..end];
+
+    const stderr = std.io.getStdErr().writer();
+    try stderr.print("\n", .{});
+
+    try stderr.print("gotLong: {s}\n", .{gotLong});
+    try stderr.print("   long: {s}\n", .{long});
+    try testing.expectEqual(gotLong, long);
 }