How to Assert Dictionaries in Unit Testing

Question

Do you know how I can Assert two dictionaries of type

Dictionary<string,List<string>>

in my Unit test project?

I tried with CollectionsAssert but it didn' work for me.I guess that it takes to simple Dictionaries as parameters(e.g. Dictionary<string,string>).I guess that the problem for me comes from the second parameter of the dictionary.Do you know how I can assert those two dictionaries?

What testing framework do you use? – Andrey Shchekin Jul 11 '13 at 11:18 — Andrey Shchekin, Jul 11 '13 at 11:18

score 11 · Answer 1 · answered Jul 11 '13 at 11:18

11

using Linq:

Dictionary.All(e => AnotherDictionary.Contains(e))

answered Jul 11 '13 at 11:18

Toodleey

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Nice...Just need to make sure to add `using System.Linq;` – saluce May 22 '14 at 06:36
This works for C# 3.0 and above. For C# 2.0 one can use: `delegate(KeyValuePair e) { return properties.Contains(e); }` – Mauricio Morales Jun 23 '14 at 17:14
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That just checks AnotherDictionary is a superset of Dictionary. Not that they are equal. – wilmol Mar 03 '21 at 09:23
Checking the Count of both dictionaries would solve this subset issue. – JardonS Jan 16 '23 at 17:38

score 11 · Accepted Answer · answered Jul 11 '13 at 11:27

11

One of the ways that would give you a good error message:

public string ToAssertableString(IDictionary<string,List<string>> dictionary) {
    var pairStrings = dictionary.OrderBy(p => p.Key)
                                .Select(p => p.Key + ": " + string.Join(", ", p.Value));
    return string.Join("; ", pairStrings);
}

// ...
Assert.AreEqual(ToAssertableString(dictionary1), ToAssertableString(dictionary2));

answered Jul 11 '13 at 11:27

Andrey Shchekin

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what if dictionary holds list of objects as values ? – kuldeep Sep 01 '17 at 08:25

How to Assert Dictionaries in Unit Testing

2 Answers2