Template-function compatibility matrix

This is the maintained inventory for HelmSharp's managed renderer. It is an implementation-status document, not a blanket assertion that arbitrary charts render identically. The golden suite remains chart-scoped regression evidence.

Baseline and method

The inventory was audited against:

• Helm v3.21.3 pkg/engine/funcs.go
• Sprig v3.3.0 functions.go, the version declared by Helm's go.mod

Helm begins with sprig.TxtFuncMap(), deletes env and expandenv, then adds its own helpers. Go's text/template also supplies built-ins independently of Helm's FuncMap. The upstream inventory records 237 names: 217 Helm FuncMap names (206 remaining Sprig names and 11 Helm-only names), the two intentionally excluded Sprig names, and 18 additional Go built-ins (slice is already a Sprig name). HelmSharp additionally retains one documented renderer-only extension, so the complete managed-renderer inventory has 238 names. The renderer's dispatch surface and focused test coverage live in HelmTemplateRenderer and TemplateFunctionTests; Helm CLI tests are optional and skip clearly when the CLI is unavailable. Direct per-function Helm CLI parity coverage for the existing supported surface is tracked by #214.

Status	Count	Meaning
Supported	165	The managed renderer dispatches the function. Focused and golden tests protect the current surface; direct per-function Helm CLI coverage is tracked by #214.
Unsupported	71	The renderer produces Helm template function '<name>' is not supported by the managed renderer.; Render() adds the template path.
Intentionally excluded	2	Helm removes this Sprig helper from its function map. HelmSharp rejects it with the same path-aware diagnostic.

Sprig v3.3.0

Supported (144)

abbrev, add, adler32sum, append, atoi, b32dec, b32enc, b64dec, b64enc, base, bcrypt, camelcase, cat, ceil, clean, coalesce, compact, concat, contains, date, dateInZone, deepCopy, deepEqual, default, dict, dig, dir, div, duration, durationRound, empty, ext, fail, first, float64, floor, fromJson, genPrivateKey, get, has, hasKey, hasPrefix, hasSuffix, indent, initial, initials, int, int64, isAbs, join, kebabcase, keys, kindIs, kindOf, last, list, lower, max, merge, mergeOverwrite, min, mod, mul, mustAppend, mustCompact, mustDeepCopy, mustHas, mustMerge, mustMergeOverwrite, mustPrepend, mustRegexReplaceAllLiteral, mustReverse, mustToJson, mustUniq, mustWithout, nindent, nospace, now, omit, pick, pluck, plural, prepend, quote, randAlpha, randAlphaNum, randAscii, randInt, randNumeric, regexFind, regexFindAll, regexMatch, regexReplaceAll, regexReplaceAllLiteral, regexSplit, repeat, replace, rest, reverse, round, semver, semverCompare, set, sha1sum, sha256sum, sha512sum, shuffle, slice, snakecase, sortAlpha, split, splitList, squote, sub, substr, swapcase, ternary, title, toDecimal, toJson, toPrettyJson, toRawJson, toString, trim, trimAll, trimPrefix, trimSuffix, trunc, tuple, typeIs, typeIsLike, typeOf, uniq, unixEpoch, unset, until, untilStep, untitle, upper, uuidv4, values, without, wrap, wrapWith.

Unsupported (62)

abbrevboth, add1, add1f, addf, ago, all, any, biggest, buildCustomCert, chunk, date_in_zone, date_modify, dateModify, decryptAES, derivePassword, divf, encryptAES, genCA, genCAWithKey, genSelfSignedCert, genSelfSignedCertWithKey, genSignedCert, genSignedCertWithKey, getHostByName, hello, htmlDate, htmlDateInZone, htpasswd, maxf, minf, mulf, must_date_modify, mustChunk, mustDateModify, mustFirst, mustFromJson, mustInitial, mustLast, mustRegexFind, mustRegexFindAll, mustRegexMatch, mustRegexReplaceAll, mustRegexSplit, mustRest, mustSlice, mustToDate, mustToPrettyJson, mustToRawJson, osBase, osClean, osDir, osExt, osIsAbs, randBytes, regexQuoteMeta, seq, splitn, subf, toDate, toStrings, urlJoin, urlParse.

Intentionally excluded by Helm (2)

env, expandenv. Helm removes both from sprig.TxtFuncMap(); rejecting them prevents chart rendering from depending on the host process environment. The environment-function-exclusion fixture verifies Helm CLI rejection and the managed renderer's actionable diagnostic.

Go text/template built-ins

The following names are available independently of Helm's FuncMap. Native template actions such as if, range, template, and with are syntax rather than functions and are outside this list.

Supported (14)

and, eq, ge, gt, index, le, len, lt, ne, not, or, print, printf, println.

Unsupported (4)

call, html, js, urlquery.

Helm-only additions

Supported (6)

fromYaml, include, lookup, required, toYaml, tpl.

Unsupported (5)

fromJsonArray, fromToml, fromYamlArray, toToml, toYamlPretty.

HelmSharp renderer-only extension

Supported (1)

mustSortAlpha. This is not part of Helm v3.21.3 or Sprig v3.3.0; HelmSharp retains it as a documented extension of its managed template surface. It is included in the complete renderer inventory and excluded from upstream Helm compatibility claims.

Follow-up implementation groups

The unsupported names are deliberately grouped into focused follow-up issues:

1. Collection, logic, reflection, and numeric helpers.
2. String, regular-expression, URL, and path helpers.
3. Date/time and serialization helpers, including Helm's TOML/YAML additions.
4. Cryptography, certificates, passwords, and random bytes.
5. Direct Helm CLI parity coverage for each existing supported function (#214).

Each implementation issue must add normal, pipeline, and failure semantics to the Helm CLI parity suite. Any intentional divergence must update this matrix and retain the path-aware diagnostic contract.